Jamie Green is unsure whether the DTM has taken the right approach with its DRS, which will make its race debut at Hockenheim this weekend.
The Formula 1-style system has been introduced, along with option Hankook tyres, to spice up the action and increase overtaking.
Drivers will be allowed one use of DRS per lap, but will not have a designated zone in which it can be activated.
But Abt Audi driver Green is unsure whether the regulation, which allows DRS activation if a driver is within two seconds of the car ahead, is appropriate.
"At Hockenheim in testing the DRS was worth about three and a half tenths of a second per lap if you used it on the longest straight," he told AUTOSPORT.
"In the DTM, usually if you're two tenths quicker than the next guy on each lap, and you're leading, it's actually pretty comfortable.
"As long as you nail the laps and hit all your braking points and apexes and don't make mistakes, you will pull away pretty steadily.
"Now, if the guy behind you is slower by that amount, but gains by three and a half tenths on the straight [provided you're not able to use DRS yourself], he's actually gaining on you.
"Given how close the performance of all the cars is nowadays, that doesn't seem quite right to me."
Green admitted that the advantage of DRS at circuits without long straights, such as Lausitz and Oschersleben, would be far less marked and could provide an overtaking opportunity that did not previously exist.
But he believes that the system is a work in progress and will be refined over time.
"Sometimes you see in F1 that DRS is too effective, like at the Chinese Grand Prix recently," he added.
"You see some guys being overtaken and then getting back ahead before the braking zone.
"But in DTM we're travelling at a lower top speed, the cars are heavier, the drag you lose by moving the wing is less, so it's far less effective a system.
"I think we'll have to wait and see exactly how it pans out and maybe it's something that will be tweaked a little if it's not giving the right effect."