Former F1 World Champion Jenson Button has spoken up in support of the FIA's ban on the deployment of the Drag Reduction System (DRS) through the tunnel in Monaco this weekend, contending that the first driver to attempt to use it there 'would have put it in the wall' and arguing that the major aids to overtaking around the narrow streets of the glamorous Principality will be tyres and KERS.

Yesterday, the sport's governing body acquiesced to drivers' concerns and announced that the DRS zone throughout the weekend in Monaco will effectively be limited to the start/finish straight and the area around the first corner of Ste D?vote [see separate story - click here]. In Button's eyes, the decision was a no-brainer.

"I think it's necessary," opined the man who triumphed in Monte Carlo two years ago en route to that season's drivers' crown, speaking during a special Vodafone McLaren-Mercedes Phone-In Session. "The tunnel is a very slippery place anyway, with a lot less grip than a normal circuit and marbles bouncing off the barriers and coming back onto the racing line. I think the first person to try it in the tunnel would have put it in the wall. There won't be any overtaking in the tunnel anyway. It would have been an unnecessary danger.

"I don't think you will see much overtaking [on the start/finish straight], but I think we will get closer, which is a bonus for other places around the circuit. I don't actually think DRS is going to make a massive difference in the race, to be honest; it will be more tyres and KERS that will help with overtaking - if you use KERS in one place and the guy behind you doesn't, he'll have a really big boost in other parts of the circuit. Overtaking will still be bloody hard, though!"

Ah, yes, tyres - one of the major talking-points in the paddock in the build-up to this weekend's action, with many predicting that the 2011 Monaco Grand Prix will likely be won or lost on strategy calls. Button estimates that there will be a difference of around a second-a-lap between Pirelli's soft and super-soft compounds, and concedes that with respect to what approach to adopt, everything is still 'very up-in-the-air' and flexibility will be vital.

"We've got a lot of testing to do before qualifying to really understand the tyres and which strategy and direction we are going to take," he reasoned. "My strategy in Turkey didn't work out; I think everybody initially planned on three stops, but went to four because they damaged their tyres, so sometimes looking after your tyres is a bad thing, because it means you don't luck into a better strategy. In Barcelona, though, stopping just three times and looking after my tyres made a big difference to my end result after such a bad start.

"I think we've got to be careful, because if we just look after the tyres and the lap times are not good, it doesn't work. Looking after your tyres is important, but there are also areas of the race where you have to push your tyres very, very hard to make a difference. We've got to have a balance, and it's difficult to find that balance because the tyres seem to be different at every race we go to.

"The strategy changes all the time and it's difficult to read, but we're all still learning and I think we are gaining more understanding of the tyres. All of that information won't make any difference here, though, because it's just a completely different circuit and we don't really know how it's going to work out. Looking after the tyres will be important in Monaco - but we just don't know how important yet."