IMO if a dog has it in him then it'll still be in him regardless of the style of training, if you have a super nasty civil defensive Schutzhund dog, the Schutzhund training doesn't make the dog any better or worse, the dog is gonna bite regardless of what you do. As long as your goal in training is to build the dogs confidence I don't see the difference between sport and personal protection, since all sport is, is control over what your dog can do anyway. A dog getting hit and hurt shouldn't be every day training, it should be a test to see how good your training has been. The only difference between sport and ppd in my mind should be that in sport you don't have as many reality based scenarios in your field training, but that doesn't mean you can't do it, it just means your dog needs to exercise the same control in the real world as they do on the training field, if your dog can't exercise that control then you don't HAVE control over the dog and is something you need to work on. At the end of the day, a good dog will bite in a real world situation, the control work required in sport is what keeps that dog from deciding for themselves what a bad situation is, and getting it wrong.
Patrick, your dog may not have a sport upbringing, but Jake is a good dog, I have absolutely no doubt in my mind about that and I was absolutely impressed with him on Sunday's training, he did the ASR routine very well and I don't think that training him to do the ASR routine will have any adverse effects on him being able to continue being the dog he is, all I see from you and Jake is that your relationship with him is evolving, you've learnt alot about Jake's mentality since I've met you, you've learnt to take a different approach to some of your training, and it's all paying off. All the crazy intense stuff you want to do with Jake can be done without adverseley affecting his ability to perform in ASR, you just need to train it in such a way that he maintains the confidence and clearheadedness that he has today. Regardless of the training route you may have alternatively taken with him in the past, at the end of the day, he's still a good dog, and he would have been just as good a dog if you had raised him for ASR from 8 weeks old, because it's bred into him, his nerves and drives are all there and they don't just go away.