is this why 'flat' got mentioned? i mean, they don't want it flat do they, they'd much rather curve it, that's why FIA added some extra tests for Red Bull, and where the whole spygate saga started. if they could curve the floor it'd be much easier to keep the flow attached and all that. Tho it doesn't really explain why they'd be disappointed in the wind tunnel, unless it's a cunningly bendy bit like they had a year or two ago that's turning out to be too cunning to really work