Like we and some of our commenters have mentioned, rear diffusers are likely to be an issue yet again this year. Ferrari is already grumbling about Mclaren's.
Of course, rule interpretation has been a part of racing forever but still, after all the chaos in court in the last couple of seasons you would have thought teams and the FIA might have worked to avoid this potential issue.
Any aerodynamicist care to comment on these pictures from today's testing? (gallery courtesy theF1.com/sutton)