Derriere garde? Lindsey?

[Forshorn]

Fans and commentators often seem to refer to Lindsey's contributions to FM and his solo work as "avant garde." Honestly, reviewing his work, I don't get this. He is firmly interested in pop, so he's hardly in the "arty" category. He seems to try to find interesting new ways of writing hooks and pop textures. Not complaining - I love that sort of thing; I believe it's called "power pop."

There are some moments on "Tusk" that are a bit like Van Morrison's "Astral Weeks" (anyone know this) musically, 'cause the main melody and the background are sort of out of key with some random notes going on back there, creating a diffuse atmosphere. Is that avant garde? 'Cause a simple pop song like "Countdown" or "Soul Drifter" isn't. Beach Boys-like arrangements like "Surrender the Rain" are not avant garde. The Beach Boys were as commercial as they come.

Can anyone explain?