I saw this in use two nights ago from DEN to LAX (plane was a 737). About four people gate-checked their stuff.

When they announced boarding, the GA asked for First Class then immediately the usual UGS and Premier spiel. The four people who gate checked were actually standing right next to the reader, and ended up going on first. Suspect the GA just told them to stand right next to him, rather then confuse/irritate the Elites with a counter published policy announcement.

It worked fine. I didn't care, as I was right behind the four, and was seated in row 1 and was not competing for overhead space.