In SFO last month I was flying a 3 class 777 to ORD. The whole gate area was full of passengers in a long line.
We were all waiting to start boarding when this guy runs up while on his cell phone not realizing that boarding had not started and was startled when he actually noticed the long line of people. He then tried to cut in front of everyone by saying "are all of you 1Ks?" It was fun to watch the reaction when a number of folks around me just as snootily said "uh yes".
He put his head down and proceeded to the back of the line.
But to respond more on point to the OP, I typically walk up after my boarding group is called and don't care about my "spot" in line as I don't typically carry on. Only once I tried to be first and that was because I was in row 1 with the bulkhead and carryon luggage on an EMB 170.