That’s really awful – can you tell us what sort of damage was done to this student so that he/she cannot play at all now? Not trying to be gossipy, just that it would be useful to keep on mental file as part of one’s professional knowledge. I’m assuming some sort of repetitive tendon damage or back strain? I can’t imagine that simply switching from Salzedo to Reni��/Grandjany (or vice versa) techniques would inflict that amount of harm, unless there are bad muscle/posture habits & tension to go along with it. Or was the injury psychological?
Poaching students is utterly reprehensible, but I don’t have any solution to it either. The problem doesn’t tend to crop up with me, not because I’m so wonderful but because no one else anywhere near my area is teaching harp. The only thing I can think of is to charge in advance by term or something similar (good discussion of this in a recent thread); and to point out to any student being lured away that if this new teacher is such a revered master, why is she/he having to scrounge for pupils at all – even without the dishonourable tactics? But I can’t come up with any suggestions except the normal common sense ones (explaining before they take on harp study that results require TIME to build, therefore not to expect that some new direction is going to work magic.)
Let us know if there’s any further followup to this sad story. It could be instructive.