More idle speculation, but presumably the very first models weren't advanced enough to have an auto-locking mechanism. Since the only difference (that I can thi

More idle speculation, but presumably the very first models weren't advanced enough to have an auto-locking mechanism. Since the only difference (that I can think of) between top- and front-loading models is the safe/disastrous result when opening mid-cycle, I can only imagine it has seomthing to do with that.