McLarens impressive pace on the first day of testing in Jerez in February was generated by a mistake when the car was being put together in the factory, Martin Whitmarsh has confirmed.
A suspension component was fitted incorrectly to the new car apparently it was simply the wrong way round and the unexpectedly low ride height that resulted happened to work well at the Spanish track. Button set the pace that day, suggesting that the MP4-28 could be the car to beat.
However once the mistake was discovered that night, it was rectified, as the car could not be run in that state long term at other venue, especially with heavy fuel loads.
Since then the team has struggled to get close to that initial performance, leading rivals and other observers to wonder just why the McLaren had been so impressive out of the box.