Again please do not try and second guess what I am going to do, but feel free to comment on what I actually do. I'm not dodging anything and have never dodged or shied away from any issue.
I have no idea why some people are capable of certain things, but I also do not think insanity or illness in the medical sense is a common indicator. If it was, then every single convicted murderer would fall foul of such diagnosis and end up in a medical institution rather than a high security Category A prison.
Let's apply this logic to other cases. Is Steve Wright insane or ill? What about Ian Brady, Dennis Nilsen, Donald Neilson, Rose & Fred West, Douglas Vinter, Ian Huntley, Robert Maudsley, Jogn Childs, etc, etc, etc. Are they all insane or ill? Or are they a product of their surroundings or are they simply warped and evil?
I'm not an expert and can only give my lay interpretation, I believe that Jeremy is guilty as convicted based on the evidence and details of the case which I have seen, it's as simple as that.
I'm not a criminology addict - despite having studied under professor Jock Young, one of the world's leading criminologists - so I cannot give you a sufficiently informed opinion on the other murderers you refer to. I have, however, studied this case in depth and my view is that Jeremy Bamber does not have the profile of a murderer, whereas Sheila, sadly did have such a profile.
Sheila was a paranoid schizophrenic who suffered a series of deep psychological disturbances and crises in the crucial developmental stages of her formative years. These crises and the damage they caused were reflected in a series of violent psychotic attacks in Sheila's teens and adulthood. There was probably a physiological element to Sheila's mental illness too.
With the exception of his adoption, Jeremy's developmental stages were not repeatedly disrupted by crises, his psychological development was therefore normal and did not follow the pathological pattern that poor Sheila's did. That's why 20 odd psychologists found that he was not mentally ill.