Should work, but UA red carpet is only open to 1K, the Plat equivalent (and the tiny numbers of UGS). The numbers difference may make the different approaches non-transferrable, although blocking off the Breezeway until zone 3 boarding starts would have to be an improvement. UA switches from red carpet lane to general boarding, and blocks off the red carpet lane once general boarding is open with a black tape "crowd control" barrier. The line is then opened indivdually for top tier elites not particularly interested in extending their on plane time. From what I've seen of BP scanner placement in ATL, the potential for UA type solutions is quite limited.

Also, had a GA in ATL yesterday, reach so roughly across an older lady during zone 5 boarding, to get my BP as I waited in the Breezeway, that I felt the need to apologize and say "excuse me" for the reach past the other pax.
Seems that the physical act of having to go over and remove the barrier from the bypass lane, the way UA does it, allows more measured appproaches. and time is not a factor, except for the first lucky few we'll all end up waiting in the jetway, anyhow.