I must lead a blessed life. I've never had a problem with line cutters or those that can't understand A-B-C and 1-2-3. I'm sure it happens, but not to me.

I come up to the line, smile and say I'm A-40. I show my boarding pass. And, the person standing there lets me get in line, either before him or after him. After that, I hold my boarding pass with the number out. Yeah, if you've got 41, you better line up behind me, but I'm not going to be rude about it. "ummm... I think you are behind me. It really doesn't matter, as we are all going to get there at the same time."

Yeah, it does matter, in terms of seating, but its a nice way to say "get behind me!"