"GB March"!?!
I just subjected myself to listening to that, and it's gay. Cheesy as hell. Never heard it before and will never again. That is classic of something that comes from the mind of the Hollywood clueless.
No. That has never been and never will be the"Official" Special Forces "march". Because there isn't one and doesn't need to be one.
When required, the Special Forces march to "The Army Goes Rolling Along" like every other solider. I can do without any of them but nobody is going to buck tradition on the Army's official march.
The Ballad of The Green Beret is ok in my book though. Evokes an era. At least Barry Saddler actually was one.