Did Dario block? Was the pinch too severe? Did he not leave enough room? Or was Sato's move simply too aggressive and opportunistic? To one spectator, it looked like a hard but fair move by the Scot; to another, it was yet another example of Franchitti's ruthlessness and willingness to wreck other cars if it benefited him. The crowd certainly made their feelings known after the race, when there were audible boos aimed in Franchitti's direction - but also many cheers.
"That last lap, running side-by-side with Takuma, I went down to give him room but we hit and I just managed to keep it out of trouble," said Franchitti.
"On the very last lap I had a good tow from Dario, I thought I had the job done," was Sato's contrary view. "But he kept pushing and didn't give me enough room so that I was well below the white line."
Whether Franchitti did leave enough room or move up to avoid a collision or not, it was in any case already too late for Sato who lost the rear of the RLL car on the low line and spun up into the wall. Somehow it didn't collect Franchitti as well in the process, but it was by inches or less.
The crash meant an instant yellow, which kicked in before the pursuing cars could catch up with the leader and meant that Dario Franchitti would lead the field around to the chequered flag under caution to claim his third Indy 500 win - ironically all of them clinched under last lap yellow flag incidents. The hat-trick puts him alongside the likes of Johnny Rutherford, Bobby Unser, and Helio Castroneves, while only three drivers (AJ Foyt, Al Unser and Rick Mears) have won four.
But in victory lane, wearing the garland and drinking the traditional pint of milk, surrounded by his cheering team and congratulated by proud car owner Chip Ganassi, not to mention his actress wife Ashley Judd, it was a two-time Indy 500 winner who was very much in the forefront of his and everyone's thoughts as it had for so much of the day: dedicating the win to Dan Wheldon, wearing the trademark oversized white-rimmed sunglasses and taking a long and heart-felt embrace from Dan's widow Susie.
Dixon and Kanaan recovered second and third place after Sato's accident, with Oriol Servia having a quietly excellent day to recover from that early unscheduled pit stop for a flat tyre to finish in fourth place ahead of Briscoe, Hinchcliffe, Wilson and Charlie Kimball in eighth.
It had been a reassuringly solid if quiet Indy 500 début for new boy Rubens Barrichello. While he managed to lead the race for a couple of laps during pit stops - no mean feat at all for an Indianapolis rookie - he was never in any real contention for the win, but neither was he involved in any dramas, accidents or sundry mistakes on his way to an 11th place finish in his first ever oval speedway event. He was comfortably on the lead lap right to the end and looked right at home at the speedway.
His fellow F1 graduate Jean Alesi had a less successful and far shorter time of it: he and the other Lotus-powered driver, HVM Racing's Simona de Silvestro, were both blackflagged just 10 laps into the race when they were already coming close to being lapped by the leaders because of their lack of raw speed, which was some 10mph off the pace of the frontrunners and outside the 105 per cent time of the front runners.
“I've had fantastic people around me," Alesi told pit lane reporters afterwards. "We were suffering with engine performance and had to pit. I would like to be back next year," he insisted.