One of the many things I thank my bruddar wanderlust for convincing me to do is to get a Red Carpet Club membership. I avoid the lines and the agents generally ask in long lines if there is someone with a short connection.

Thank you bruddar wanderlust.

But if I don't have a club membership for flying on another airline... I will try to check in at the gate.

Maybe I have an answer:

*About a half hour before the 10-minute/shut doors rule set up a separate check-in area that says "30 minute or less connection." Agent send the passengers to this exclusive line.

Don't know if it's practical for carriers in non-hubs or in smaller airports, but it's worth a shot maybe?