I feel that I should preface this review with a dirty secret: Hot Tub Time Machine (heretofore to be abbreviated as HTTM) is my favorite guilty pleasure film of all time. HTTM is not a great movie, I’m not even sure that it’s a good movie, but it is a retardedly fun time travel romp. Part of the charm is the nostalgia (John Cusack making another 80s flick), part of it is how far they take the comedy bits (which is needless to say, they take them to the most…