UPDATE SUNDAY, 8:17 a.m.: Conventional wisdom holds that you don’t release sequels two decades apart, particularly in a lighting-bottled genre like comedy. But wisdom has never held much sway in the Dumb and Dumber franchise, which returned after a two-decade dormancy to engage in a nip-and-tuck battle with Big Hero 6 that underscored the muscle of raunch this year at the box office.
Dumb and Dumber To looked to take the derby this weekend from a BH6 in its sophomore…