Mercedes ended up completing 675 laps across the opening four-day group session, 228 more than second-placed Toro Rosso in the lap count. So “unprecedented” was the double world champions’ mileage that the German constructor elected to change its testing schedule to avoid putting any physical strain on its drivers.
“It’s just been an incredible week of testing for us and before we came here they were talking about doing 800km a day and I thought that was crazy because I’ve never done that in the past,” Hamilton said after racking up 343 laps himself.
“Usually you have breakdowns in the car, but even not just for us there is no breakdowns and a lot of reliability, which I guess you would expect with the third year of these regulations.
“Just the strength of [the W07], it just keeps going and going and going. To think we won the two world championships and going into a third year you would think it is so easy to lose focus, but everyone has done an even better job with delivering the whole package.”
Hamilton only posted the 12th fastest time overall this week, with team-mate Nico Rosberg eighth in the aggregate standings. However, the softest tyre Mercedes ran on during the first test was Pirelli's medium compound, while Ferrari and Red Bull set their benchmarks on the new ultrasoft.
Asked about the ultimate performance of the W07 and his prospects for a fourth world title, the triple world champion replied:
“I personally feel physically good. The training has been hard work and I’m getting older! But the car looks fantastic, we don’t know the pace of the yet but what we can say is that it will go the distance. That’s half the battle, but I don’t think it’s slow.”
Hamilton and Rosberg will keep alternating testing duties action pre-season action resumes in Barcelona next week.