And it is poor form in a lineup. It has nothing to do with manuevers or even outrunning the pocket while on the wave. Using a craft's wave catching ability to hog waves is a major source of tension amongst surfers. It can be tough to sit in the lineup when you know you can catch a wave earlier, but sitting well outside of everyone else makes you conspicuous in a "watch out for that guy" way. Not only do you cheat others out of waves, you are cheating yourself out of the thrill from the drop. A late, steep takeoff that you might not come out of is a rush!
I took the Reaction to Mase a couple of weeks ago with some friends. Being an semi-epic day, it was pretty crowded, so I sat at the end of the lineup with a SUP surfer so as to be less intrusive. I was nearly a non-factor for the boardies, got every wave that I wanted, and had a ball!