I've always thought that the idea Sheila could have wounded herself with the first shot then ran upstairs sounds like something out of a bad horror film. The fact that there was no blood having run down her chest proves this could not have happened. And do people on the Tesko forum think she had a shower after wounding herself in the throat non fatally?
Incidentally if Mike was on the same wing in jail as Bamber surely he must have been in prison for a pretty serious offence. Do we know what Mike was actually in prison for?
What particularly fascinates me about Bamber is that he spent a lot of time with people like Mike and Aunt Agatha convincing them of his innocence. When he felt they had outlived their usefulness he cut off all ties with them, however, Mike and Aunt Agatha still remain fiercely loyal to someone who has not exactly been particularly nice to them. Why is this? Is he someone who is adept at charming people and being able to manipulate and control them? With this in mind I have no problem with the thought that he could have persuaded Julie to keep quiet about what she knew for so long, and even that he could have persuaded Sheila to lie down while he shot her.