It used to be that the short ovals were the places that sent tempers in NASCAR into overdrive - the half-mile at Bristol Motor Speedway was notorious for its fiery on- and off-track fireworks and confrontations.

But in a season that has been rather tame for such matters (outside of the ongoing Richard Childress Racing vs Kyle Busch smackdown) it seems that in 2011, if you want road rage then you need a road course, as both Infineon Raceway and Road America proved this weekend for Cup and Nationwide races respectively.

The Nationwide event over in Wisconsin had looked to be quite a calm, straightforward affair - until the last few laps exploded into something of a demolition derby and resulted in three attempts to finish under green/white/chequered (GWC) conditions.

Jacques Villeneuve - who had already been given a mid-race penalty for changing lanes too early at one restart - made a rash lunge down the inside into turn 1 from fifth position at the first GWC restart, only to find third place man Brian Scott taking up the space he needed. The ensuing collision not only put Scott into the gravel but also caught up Max Papis as well.

"A little bit aggressive," Villeneuve admitted about the restart. "The track narrows before turn one and I just ran out of road, put the wheels in the grass, played bowling there, took the two cars out and made a few people unhappy ... When I put two wheels on the grass, I really didn't want to be there.

The next GWC saw leader Michael McDowell spin and trigger a multi-car wreck, and the third and final restart attempt saw McDowell and Aric Amirola spin and mean the race did finally finish under caution after all, by which time Villeneuve had managed to recover to third place once NASCAR had spent a long time trying to determine exactly who was ahead of whom when the yellow came out from the mountain of data and video footage.

It all proved to be something of a premonition and a warning for what was to come the following day in California.

At Infineon, one of the first signs of fraying tempers came from polesitter Joey Logano, who had been involved in an increasingly physical and bad-tempered mid-race battle with Robby Gordon. Finally on lap 53 he had had enough, lined up the #7 in his sights, and piled straight into the back of Gordon on the approach to turn 11 until the car spun off and dropped to the back of the lead lap.

"He was running me all over the race track," explained Logano afterwards. "He knocked my fender in for no reason. We were a lot, lot faster than him. I just had enough. I wasn't going to get pushed around. He pushed around before and I was sick of it. I think that's a small story. That's not a big deal."

No doubt Logano's crew chief, two-time championship winner Greg Zipadelli will be applauding his driver's action. Zipadelli has reportedly been frustrated in the past by his young driver's lack of assertiveness on the track, and insisted that the 21-year-old "man up" and make sure he got some respect from the other drivers. This weekend at Infineon surely achieved at least a little in that direction.

Then there was the case of Juan Montoya, who did nothing to dispel the crude stereotype of "hot blooded Latin temperament" when the red mist descended late in the race. He seemed determined to work his way to the front no matter what the cost to those around him, gaining multiple positions after the final round of pit stops until on lap 97 he came up on the back of Kasey Kahne going into the turn 2 right-hander. Kahne wasn't about to let him through, and Montoya forced him off onto the grass - losing positions himself as a result.

"Montoya just drove through me at the top of the hill. That was obvious," Kahne said. "I got hit from behind, just driving into the corner. He got mad because I beat him into turn one when he was beside me in turn 11. So he got mad and just wrecked me in 2."

Montoya regrouped and tried to make his way back up the field again, only to come up against Brad Keselowski a few minutes later. The two of them went into turn 3 side-by-side with Kyle Busch immediately behind them, Montoya having the inside line and allowing the #42 to drift out forcing Keselowski to put two wheels onto the dirt. Keselowski took exception and sent Montoya for a spin.

"I don't take any pride in all that stuff, but at some point, you've got to run your own deal," Keselowski said. "It was pretty obvious that it was eat or be eaten, and I wasn't going to be eaten."

"We got through the corner, and I just got on his bumper a little bit and moved him a little," Montoya admitted, but said he didn't deserve to get spun in revenge. "Got a good run, and I guess he didn't like it ... he just plain and simple wrecked us." Although he recovered to the track in 12th place, "I just killed the tyres when I spun," and he ended up 22nd by the end.

Perhaps the driver with most reason to be angry about the incident was Kyle Busch, who had no where to go when Montoya and Keselowski crashed and who followed the #42 off onto the dirt for a spin. However, Kyle seems determined to lower his controversial public profile at the moment and fly under the radar, and his comments were conspicuously inconspicuous: "We were like a fourth- or fifth-place car. We had the opportunity to finish there, but unfortunately with about five to go we were involved in a few others wreck and spun out," he said as blandly as possible. "Gathered it back up and got going again, probably fell back to 15th, but salvaged an 11th out of the thing. We'll take it and go on."

Strangely, given that it was the headline bout of the weekend, the one on-track battle that generated least off-track heat was the one between Brian Vickers and Tony Stewart. Good friends off the track, they seemed to regard their altercation at Infineon with a large dose of professional distance - just one of those things that had to be done for the job, but which they took no pleasure or satisfaction in.

"I've been complaining about the way guys have been racing all year," Stewart said after propelling Vickers down into turn 11 and into a multi-car collision and spin on lap 39. "I like Brian. I'm not holding it against him at all. I don't care if it was [my team mate] Ryan Newman; I would have dumped him, too. If they want to block, that's what is going to happen to them every time for the rest of my career."

"I wasn't blocking him. That may have been his perception from where he was sitting, but the #18 went off the race track in front of me," Vickers said in response. "He was going off in the dirt and then coming back in front of me on the race track, and I was trying to avoid him ... I think when [Stewart] sees the replay and he realises why I went low - if he looks at it out of my front windshield - he'll realise it had nothing to do with him. It had to do with the #18 almost wrecking me, and a couple of other guys running slow up top."

But that didn't stop Vickers cooly setting up a revenge encounter at the same point on lap 87, barging Stewart so hard that the #14 spun backwards onto the top of the tyre wall.

"He made his bed at that moment [on lap 39], and he had to sleep in it," Vickers said bluntly. "He wrecked me, and I dealt with it."

"I dumped him earlier for blocking and he got me back later on," said Stewart, sounding less less angry than resigned about the payback. He was also resolute about his initial actions: "If they block, they are going to get dumped. It is real simple. I mean, I don't blame him. I don't blame him for dumping us back.

"I don't race guys that way. I never have. If guys want to block. then they are going to wrecked every time. Until NASCAR makes a rule against it, I am going to dump them every time for it. He did what he had to do and I don't blame him. There is nothing wrong with it."

As for NASCAR, they seem content that this lies firmly under the auspicies of "Boys, have it" - their philosophy that the drivers will police themselves and keep each other in line with at times tough love when called for. As a result they didn't intervene at Infineon and gave no sign of any post-race penalties either: what happens on the track, stays on the track is their current mantra.

That even seems to apply when one driver's deliberate enforcement action against another - such as Stewart's against Vickers - then ends up involving innocent bystanders in the process. Dale Earnhardt Jr. was involved in the ensuing multi-car incident on lap 39, a hole in the radiator causing his engine to blow and causing him a costly DNF in 41st position. At least when Vickers and Logano sought their own 'retribution' they made sure they did it when no one else was around to get caught up in the mess.

NASCAR asking drivers to be law enforcement, judge and jury may be asking too much of the drivers, even of Stewart who is one of the most senior and respected of them as both a former champion and now as a team owner/driver. While he feels justified in his actions, acting as NASCAR's top cop on track proved very costly to him - the final encounter with Vickers causing him to retire in 39th place, a huge hit to his Cup chances as it means he drops to 12th place and out of the Chase qualifiers: he has only missed the Chase once since its introduction in 2004.

Wouldn't the sensible approach be to play it safe, hang back, and get a reasonable finish? Not according to Stewart: "It didn't make sense to [block] and I'm not going to tolerate it. I don't race guys that way and I'm not going to let anybody race me that way," he insisted. "If they block they get dumped. Plain and simple."

Will it mean drivers now give Stewart more room on the track and stop the blocking - or will it make the #14 a marked car instead? Whether his new "take no prisoners" attitude will help Stewart on track or hinder him remains to be seen. His peers in the sport, championship leader Carl Edwards and four-time Cup winner Jeff Gordon, had their own views.

"I don't think I've ever gone out and tried to get somebody back," said Edwards, but he was broadly supportive of NASCAR's line on such matters. "I think NASCAR has this 'have at it' mentality, the statement they made. I think in the end it will be better and safer for all of us. You know when you're out there, if NASCAR is going to let things be settled on the racetrack, I think people will respect each other a little bit more on the racetrack, and that's good."

Gordon was more mindful of the Championship implications for drivers like Stewart who took on the role of teaching others the hard rules of on-track life.

"If you're going to try to win a championship, those types of situations are, in my opinion, going to hinder you from doing that," he said "If you start getting into a battle with a guy, especially if it's somebody that is not in championship contention, you know, then what happens is you're not going to win. It's going to be a lose for you and everybody. If it's somebody that's in the championship, then you guys have to figure out how to settle it, whether it happens on the track or off the track."

Gordon pointed out that everyone was different, "Some people have short fuses and some people have long fuses", and recalled that he'd had his own on-track falling-out with Stewart in the past - and had no desire to ever get in that position again.

"That's not a guy I battle with anymore. We had our situation. I'm so glad that we resolved it fairly quickly. Nobody has more respect for one another out there than me and Tony because I've been on the other side of it with him when he can get mad. He's not a guy that you want to have gunning at you. He's a great race car driver, he's smart, [but] he can get really mad."

With his "Don't make me angry; you wouldn't like me when I'm angry!" message, maybe Stewart ought to switch to an incredibly green livery for the rest of the season.