i think the issue is more than when you try to negotiate, this is what happens.
club A tells you they want £80m
you only want to pay £50m
you faff around and send offers that get rejected, and eventually someone else comes in and meets club A's price and its done.
that isnt to say that we should only be trying to buy players that have release clauses, but more that if we are going to try and save a few million pounds, we probably shouldnt bother, assuming that player is wanted by others. and if that player isnt wanted, then id have other questions to ask as well.