Neil, I'm pretty sure in that video I did on the hands, I explain as I massage that the fingers/hands claw in as result of the wastage of the muscles in the lower arm, and that's why my technique does so much work there before attempting to stretch the actual fingers.
You may slow it a little, and certainly you can alleviate the resulting tension and make it easier to keep the hands clean and dry if you use massage and/or splints. I wish I could tell you these strategies could stop the nerves from dying, but this is of course what is causing all the issues.
How far it will go is another of those things we can't answer, definitely some PALS have less of this depending on which nerves completely die first. So I'm sure some PALS could report that they only had some curling/clawing of some fingers to some degree and others report full hand impacted.