McLaren has ruled out racing a passive double DRS for the time being, because it believes bigger performance gains can be made elsewhere on the car.
With Lotus having confirmed earlier this week that it hopes to race its passive double DRS this season, it had been expected that a majority of frontrunning outfits would pursue the concept for 2013.
But speaking at the launch of the new McLaren MP4-28 at Woking on Thursday, McLaren technical staff reckoned that difficulties in getting a passive double DRS to work effectively had left it reluctant to devote much time to it.
When asked by AUTOSPORT if McLaren was pursuing it, director of engineering Tim Goss said: "We've been looking at such systems for a couple of seasons now and, as you have seen, we haven't run one yet - so heavily pursuing it would not be the right description.
"It is not straightforward to get them to work effectively such that they give you a net performance gain.
"There are parasitic losses in doing such systems and, as you will notice, there are three teams that tested them last season and no one actually raced one."
McLaren sporting director Sam Michael said it was the difficulty in getting the system to operate reliably, especially the speed at which the fluidic switches are turned on and off to change airflow to help stall the rear wing, that was the key factor in his team steering clear for now.
"They are extremely sensitive and difficult to make work," he said. "It is definitely an area that will, in time, become more and more exploited. But we are right at the beginning of it - and there are other bigger gains and bigger fish to fry before that one."
As well as pursuing a different path from Lotus on the passive double DRS, McLaren has elected to race with a 'vanity panel' covering a stepped nose on its 2013 car.
Goss was adamant that smoothing the airflow in that area of the car was more of an advantage than the disadvantage of extra weight on the car, which is why Lotus has opted not to race it.
"Aerodynamically you would not put a step on the top surface of the nose through choice, it is an artifact of the regulations," said Goss. "So we don't...
"It is a lightweight structural cover. There is no structural significance at all, so it weighs very little.
"I think James [Allison, Lotus technical director] left it quite open as to whether they would do something.
"If we look aerodynamically at the step on the nose then, to be honest, it is not very significant but you will pull a few minor losses off it. You would not do it [have a stepped nose] out of choice, so we don't."
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