Fred Sweet runs dancing classes for middle$-$aged and elderly people some of Fred's customers lack physical coordination and injuries from kick balls etc. are common Fred naturally fears that injured customers will sue him for negligence that he makes each custom sign a written contract containing a clause relieving Fred of all liability for injuries suffered during his dancing classes however fearful that he will lose business if potential customers become aware of his strategy Fred states the clause and fine prints and doesn't point it out to them and injured customer sues Fred in negligence Fred wants to defend on the basis of the clause in the contract which of the following is the biggest weakness and Fred's position