It's not that you're questioning things, that's fair enough. However, I very much doubt that the suggestion that Bonnett simply 'forgot' he not only spoke to Nevil but logged a call from him. Later recalling that it wasn't from Nevil at all, it was from a police officer, someone he'd had never met and yet he knew the guys call sign.
Actually I do agree with you that, on the face of it, it is doubtful that Bonnett could have forgotten, but I do not accept that it is impossible. I also maintain my central point about this evidence: our task here is to weigh up the quality of doubt that the documentary inconsistencies raise.
That said, let us consider the subject of memory and psychology. Here I can start by applying general life experience: I know that:
- people do forget obvious and glaring things, including things that have happened in the previous few minutes;
- most people are highly-socialised and have a tendency towards group think and peer pressure, and most people allow these dynamics to greatly influence memory;
- Bonnett was a night worker. I have worked nights: it detrimentally affects memory.
Then we can look at academic knowledge of the subject of memory and psychology. It's been established in controlled studies by academic and professional psychologists that people will swear blind that X is Y if everybody else in their peer group says so, even though their own immediate recent experience doesn't support this. Almost-all of us are susceptible to this flaw: regardless of our IQ level or general intelligence, we will - at times - go along with the group consensus in defiance of our own experiences. It's the way we're wired.
Note: I am NOT suggesting that Bonnett is lying. I don't need to. Anybody reading those logs will deduce, prima facie, that there were two callers not one. Again, that does not mean there were two callers. I may even agree with you that there was only one caller, but that is not what the logs say and remember, here we are considering not so much what we as individuals 'think', but the matter of legal doubt.
Bonnett could easily have taken a call from Nevill, recorded this accurately so far as it went, then got swept up in the seriousness and urgency of the incident, and in all the confusion forgotten about the first call and in his mind merged everything into one call from PC West only. He then doesn't come under scrutiny until many weeks later, by which point it is believed that there was no call from Nevill.