New race restart regulations introduced by the FIA allow race director Charlie Whiting to consider, based on track and weather conditions at the time, whether to use a standing restart over a Safety Car restart.
Previously all restarts following a red flag were done behind the safety car which would complete a number of laps leading the field before pitting, but Whiting will now have the option of a standing start if conditions are suitable.
To test these new restart procedures, standing starts were simulated during testing on Tuesday and Wednesday at the Circuit de Barcelona-Catalunya.
Haas driver Romain Grosjean was less than complimentary when asked if he had found any issues with the new regulations.
"Yes. I didn't go above fourth gear. It's un-driveable," he said, referring to his tyres which had already completed a number of laps. "I was one of the first guys to come on the grid so I sat there with [Valtteri] Bottas for a long time. But when we restarted, it was like it was raining on slicks.
"Every time you upshift, the rears spin and wheelspin. Every time you downshift, the rears lock. You go into a corner and slide. It's doesn't work. Safety-wise, I'm a bit concerned because as I say, I went to fourth gear and that was the maximum I could do.
"It's pretty cold, but we know that if you spin and then you restart and you try to push again, the tyre's are normally gone and you never put the temperature back in. So imagine doing a slow lap and then aborting and then another one. We were down in 40 degrees or something like that with the tyres. They just don't work."
Grosjean, once seen as the precocious wild child on the grid during his rookie years, was scathing about the risks drivers would face with the new regulations if they were implemented for a restart.
"To me it could be carnage!" he added.
"You can lose the car in a straight line, and if someone loses it and then people are behind… We tried it, and honestly I was not having much fun just trying to up-shift and downshift, it was tricky. Bottas was in front of me, and he was not having much fun either. I don't know what pace we've done, but look at the sector. It's going to be very, very slow."
When asked about what he could do about the changed procedure, the Frenchman said he would approach GPDA boss, and former Benetton/Williams F1 driver, Alex Wurz to poll the rest of the membership which now includes the entire grid for the first time.
"Yeah I'm going to speak with Alex. I've got a GPDA group message. I'm just going to say, 'Look, [in] my experience, I feel like it's dangerous.' Maybe the others don't feel the same, but I don't feel confident going with these cold tires."
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