“This time is worth nothing as is the one I set yesterday and those of the previous days,” said Fernando. “Yesterday, we worked mainly with the hard tyres and the others ran the softs and we were seventh. Today, we fitted the Softs and maybe the others did not and we are first. That’s all it is.
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I wonder if they spent so much time (the first 3 days) running the harder tires and therefore setting comparatively poor lap times because they want to make sure there's not the performance gap they suffered from last year with the F150 running the medium and hard compound tires.
The F150 seemed like a different car when it wasn't on the softs or super softs, especially in the beginning half of the year. If I were them, I'd be spending a lot of time working on the car with the harder compounds too.