I was asked an opinion on this on yesterday.
East had SKJ98; HKJT; DAKJ9; CT4
All NV, S opened 2d described as "our strongest bid, Benji". Full contested auction was: 2d!, 3c, 3h, 4c
It turned out that South's 2D was in fact a weak 2, and 3N + a few was the normal score for EW.
On the face of it simple. NS had no convention card so the benefit of the doubt was against NS deeming a mi-description and not a misbid. So EW damaged, and with correct information E would have bid 3N instead of just competing in 4C. Correct to some combination of 3N+1 or +2.
BUT, is not E in some way culpable? Should he not be sniffing a rat and asking for clarification as there are clearly a lot of points in this pack. With 16 points opposite an overcall he arguably has a 3N bid anyway, from which he can run to 4c if S doubles.
Or can he just have the "double shot" of bidding 4C and if it turns out that it is a mis-description then complain to the TD for damage and correction? E can be described as a "seasoned club player"; not expert and far from a beginner.
We pragmatically felt it best to advise him that we suspect him of going for a "double-shot" against he would not be viewed so favourably, and to adjust to a score that gave him an average, whereas he wanted 3N+2 for a joint top. Not exactly "book" procedure but we felt pragmatic and just.