I'm not sure that this is what you should infer, to be honest. This would apply when there is an overbooking situation, and some other poor low-or-no status sod will be downgraded or involuntarily denied boarding when BA flogs more tickets than it has seats for.
However, hoping that somebody else will be chucked out of their working seat to accommodate you is taking it too far, I would suggest.
I was more thinking that volunteers could be asked for as the flight as effectively oversold with one seat u/s - I've stepped forward myself before and happily accepted travelling on a later flight if it suited my plans.
If the "Premium Manager" at the gate had explained to someone that they'd be moved but get 75% of their ticket back, I can imagine that there might have been some takers. She in fact said that she was there to talk to me "... as I was a GCH", which is nice but she didn't stick around to make sure I was rebooked.
Sorry for attracting the FT flamethrowers
and I have read enough of the DYKWIA thread to make sure I stay away from that kind of behaviour
Apologies!