It really doesn’t bother me when people drop or round out the ‘t’ in “often.” Rounding is better than dropping off, but really, you sound kind of pretentious if you of-ten pay at-ten-tion to split-ting the syllables in words like of-ten.
Seriously though, if you drop the ‘t’ in “enter,” I feel it is safe to assume that you are not at all as competent as you appear. I don’t think this is just me. It sounds dumb. For example: