Oh Carl, the more is...I'm just skittish as hell about the risks of self gaffing when rope climbing wearing spurs. I have to admit this newish trend is not one I have tried, nor even seen used, but the several truly unpleasant self inflicted wounds I've witnessed, or seen documented, or been asked to investigate as a USFS master climber, convince me that sooner or later (and I lean towards sooner) some poor climber is going to gaff the shite out of themselves rope climbing with gaffs on.
The reason I'm convinced that this injury will occur is the decades of experience I have in SRT rope climbing without gaffs in the mix. I've banged myself any number of times, one boot against the other leg. I've trained newbies wherein that sort of banging was just about inevitable on more leg strokes than not. I know you and the many others going this way are far from newbies...but I've seen too much of this sort of contact to ignore the risk, as I see it.
It's going to happen if this method gets much traction, imo. I don't expect my little voice in the wilderness will change anything on the trajectory of it, but as an old friend I beseech you... don't let it be you.