In John E. Gregory and Son, Inc. v. A. Guenther and Sons Co., Inc., 432 N.W.2d 584 (Wis. 1988), the Supreme Court of Wisconsin explained its reason for rejecting an exception for unreasonable delays not contemplated by the parties under Wisconsin law: Delay 'not contemplated by the parties' is not an exception to the general rule that 'no damage for delay' clauses are enforceable. We conclude that parties can mutually assent to such a clause without contemplating in particularity all of the potential causes of delay. Indeed, the adoption of a 'no damage for delay' clause shows that the parties realize that some delays cannot be contemplated at the time of the drafting of the contract. The parties include the clause in the contract in order to resolve problems conclusively should such delays occur. The parties can deal with delays they contemplate by adjusting the start and completion dates or by including particular provisions in the contract. 'It is the unforeseen events which occasion the broad language of the clause since foreseeable ones could be readily provided for by specific language.' Thus, the doctrine of mutual assent supports our conclusion that delays not contemplated by the parties should not be an exception to the rule that 'no damage for delay' clauses should be enforced.This result is neither unfair nor inequitable. Knowing that unforeseen delays...can occur, parties can bargain accordingly. A subcontractor can protect itself from the risk of unforeseen delay simply by adjusting its bid price in recognition of the potential additional costs or by refusing to accept such a provision in the contract." (Gregory, 432 N.W.2d at 587.)