There are a lot of useless clauses in contracts, that is to say clauses which have no specific effect, from a legal point of view. Nevertheless, this king of clauses can be useful when economic actors are elaborating the contracts (they provide information for instance) or when a contractor wishes to enforce the contract (a particular de facto power may come from a useless clause).
BOUTHINON-DUMAS, H. and MASSON, A. (2012). Les stratégies juridiques fondées sur les clauses inutiles. In: Stratégies juridiques des acteurs économiques. 1st ed. Larcier, pp. 399-422.