Do not ask to have the cards placed unless it is solely for your own information.
A player has not the right to have the cards placed after they have been touched for the purpose of gathering them.
It is unfair to revoke purposely, or to make a second revoke in order to conceal the first.
The revoking side cannot win the game on that hand, nor score more than 28 points.
Clubs is a safer declaration, holding four with two honours, than spades, when but one or two are held without an honour.