Originally Posted by EIPremier

Perhaps elite boarding slows things down slightly, but I don't think that's the main issue. It's the fact that people still try to take too many carry-ons on board. Even my soft-sided bag which can often times fit underneath the seat, they still insisted on gate checking. On the A319 I was flying, everyone in Group 5 had to gate check their bags. The only reason I was in Group 5 is because I didn't get to the gate until 20 minutes before departure.
We were all left standing in the jetway while they fiddled around with tagging the bags and finally gave us claim checks. This wasted at least 10 minutes. In the end, they closed the door about 5 minutes prior to sched and pushed back 2 minutes early.

Without the gate checking, they would have completed boarding in under 15 minutes.