Ya it would be a good idea. If say in the very unlikely event Man United do get a points deduction, having signed Cunha his contribution would more than likely result in them gaining more points than what they would get deducted. If the PL blocked transfers it would impact the bigger clubs probably more than a points deductionShouldnt part of the ruling be like it is in Spain or Italy (not sure which one, or if I've made it up), but before you actually sign a player you need to show you are at that current point in time...compliant with the laws that could be put forward at a later date.
E.g Utd know they could take a PSR knock, but feel its worth it to get the player on board, but in other country's the league wouldn't sanction the move