Sebastian Vettel has questioned the decision to allow two DRS zones in the Canadian Grand Prix, arguing that it made overtaking in the race too easy.
The Montreal race marked the first time that the FIA has allowed for two DRS zones, with the first coming on the run to the final chicane and drivers then allowed to use the system again on the start-finish straight.
Although poor weather meant DRS wasn't enabled until the 46th lap of the race, there was a noticeable increase in moves for position once the system had come into play.
Michael Schumacher in particular lost out due to the use of DRS as both Jenson Button and Mark Webber were able to sail by the run to the final corner and Vettel said Canada may have been an indication that the Drag Reduction System can make it too easy for drivers to overtake.
"In the end you have to be careful about how big you create the zone because obviously it can make overtaking too easy, like I think it was in Canada," he told ESPNF1
. "If you are right behind and you open the wing then the other guy has no chance to defend, which is surely not the idea. But we are playing around and it is a new system. We are still early in the season and everybody is still learning with it."
Vettel added that his mistake on the final lap, when he ran wide and allowed Button through to win the race, had come about partly because of a need to push to ensure that the McLaren driver couldn't use his DRS on the final lap.
"I think in the conditions I obviously had to push very hard to stay ahead and I tried very hard to keep the gap for the back straight," he said. "Because the thing is that once Jenson was close in the DRS zone then it would have been just too easy to overtake and he would have gone past no problem."