What I've noticed is a continued lack of consistency in when [pre]boarding begins? IMHO, this problem appears to be confined to MSP, but with most of my travels on 753s, sometimes I'll stroll up 40 minutes prior and be able to walk right up.

Other times, I'll show up 30 minutes prior, and they have yet to start pre-boarding.

Still other times, I'll show up 35 minutes prior, and stand in a long queue. Friday, I showed up 35 mins. prior to a LAX flight on a 755, and ended up waiting 15 minutes to board...