TC - congrats on the new job - do pm me with details.
Very happy in my new role
I think this technique is only suitable for VRS, definitely not for SWP as you are already decaying the Nr as you overpitch which, as you say, degrades TR thrust markedly.
I know yaw variations can be a theme of VRS due to the 'bursting bubble' disruptions from the MR upwash and, in this case, the TR would be less effective.
However, not every episode of VRS will give those symptoms and it will vary with aircraft type. Equally not every excursion into FDVRS will give Nr decay - that will only happen if you keep pulling until you hit engine limits.
It may be that this technique has some validity in some circumstances and it certainly can't make things worse if you are limited on recovery height available.