One question Mason.
What was Sheila doing when Neville made his 'mysterious' call to Jeremy ?
If it is in you're book, you do not need to answer. If it is not in you're book, you need to answer.
I created a thread on this recently. No plausible answer was given.
Neville's implausible words suggest Sheila was about to or had already started shooting people. Neville then deciding to ring Jeremy !!! 
If there is no realistic possible answer to this question, everything else is irrelevent.
Nice question Adam. I shall do as you ask, and therefore shall not answer. However, I wasn't there, nor were you (at least I hope you weren't), so its pure conjecture based on nothing but 'allegiance' whatever anyone claims.
Many people proclaim themselves 'experts' in this case, reality is, people are basing so called 'new evidence' on the inarticulation of others, or police cock ups - which, unlike you seem to accept - are very common, sadly all of this affects innocent and guilty lives. Yet people want to believe the system is flawless - believe me, it isn't. People won't accept this because its scary, it goes against the grain, they want to feel safe and secure. I worked in the police for three decades, I hasten to add - with an unblemished record. But would I trust a coppers word then or now, no I wouldn't. Some, it has been proven in court, would rob their own family all for the sake of money.
People are dicks in all walks of life, not only in the police, look at politicians, councillors, thespians, singing stars et al, for me, that's what makes the world such an interesting place - liars, cheats and oddballs exist in walks of society, they are not exclusive to the incarcerated criminal community. Despite this, I believe most people are rightly in prison, as we now know, those who shout loudest about their innocence aren't always what they seem. Jeremy Bamber was found guilty on evidence in a court of law, thats a fact. The question remains, was the provenance of that evidence true?
You can make all the claims you like and copy what others say because it sounds acceptable, you even say you read book reviews before you buy a book. Let me tell you most book reviews are penned by people fuelled with jealousy and insecurities, many are known to the author, writers used to accept them, but no longer, why? Because people no longer put their name to them, they lack credibility without the provenance of real identity.
Sad thing is, until you actually research this case, live it every day and night for years, listen to Jeremy Bamber, the police, witnesses, barristers and people it affected, I've done them all, then you cannot appreciate the pressures all of these individuals endure.
Opinion is great, I accept it, but living with this case day and night as I have, and there are a few people on here who know what I've gone through, makes you take stock and realise the traumatic affect that still endures. I had no allegiance at the outset, I have no allegiance now, I have researched this entire case objectively. I get on well with Jeremy, we laugh and talk together, but then I laugh with Ronald DeFeo too, he admits he murdered his family, each year I get cards off the Lord Chief Justice of England and Wales, and serial killers such as Peter Sutcliffe - juxtaposition of morality or what?. In this case, me and Jeremy are two different people, I absolutely liked Stan Jones when I spoke to and interviewed him, doesn't make either Stan or Jeremy right in what they may or may not have done.
Jeremy is the only person on this planet who knows the truth, not the relatives, not the courts, not the media, and certainly not the red. The evidence at court was crap, you know it, we all know it, however, that means nothing because a jury of Jeremy's peers, lay people who were not instructed correctly, believed it. Therefore it all becomes fact. In most circumstances, without such pressure, most people would err on the side of caution, jury's cannot, pressure is on them to deliver a verdict.
That's just my thoughts Adam, I know you have your own but trust me, an open mind is the best one to keep in everything involving the establishment, its my belief there is no such things as coincidence. Things do get contrived.