Ferrari driver Felipe Massa believes the new rules for next season will lead to more accidents on wet races.
Driver aids have been banned for 2008 and all teams spent three days at Barcelona preparing their cars for the new regulations.
Massa said drivers will need to be a lot smoother next year, and has warned the lack of traction control is likely to lead to more crashes.
"It's interesting," Massa told Gazzetta dello Sport. "The throttle used to be like a button, you'd lift or floor it with no half measures. Now you need to be as smooth as possible.
"The laptimes have been good immediately, that's a sign that we've started on the right footing.
"But from a safety point of view, these limitations in the use of electronics look like a step backwards to me: in the event of wet races we'll have a lot more accidents. "