Thank you for your very informative post, a lot of it rings true with soots, I feel that he has adjusted to his eyesight quite well, although he could still be insecure and frightened, I can only imagine how I would feel if I were in that position.
I really am stuck with him as, as soon as I have a theory something happens to contradict it (lack of congruence - thats an in word for any psychologist / therapists), basically because his behaviour is unpredictable, although this could indicate a biological cause. I also feel that (at this moment) he has a good quality of life, and that if he is "tormented by demons" then it is only for brief periods of time, and not enough to justify pts, however if his condition worsens then it may have to be an option, however I'm very much hoping that this is just a temporary blip.
Today he has been ok but tried to bite me when I was towelling him down after a walk, 15 mins later though I was playing and handling him without complaint!
The vet cancelled our friday appointment so were going to see him monday.