Correct me if I'm wrong, but isn't a locking pocket knife, despite being much safer, an illegal item to carry?
You are wrong. What happens is that the court makes a judgement as to whether the knife is being carried as a weapon or a tool. A short, non-locking folder is presumed to be a tool, and a fixed or locking blade is presumed to be a weapon, but both presumptions can be rebutted. There have been recent cases of people arrested for locking blades, where the case was tossed out of court and the police embarrassed.
Isn't it true that knives with points of any blade length have been banned, or their banning discussed, in that various Parliaments of the United Kingdom?
It is not true that they've been banned. I don't think the banning has been discussed in parliament, either. The idea was raised by, I think, a doctor, and it got a lot of publicity precisely because it was considered outrageous. Newspapers like to wind people up. The controversy is why you have heard of it.
Personally I think it would be a good thing if it were discussed, and the whole area reviewed. The statute law is good, but has been followed by some bad case law which needs clearing up.
Is not the determination of "good reason" left at the hands not a jury, judge, or prosecutor, nor defined by law, but an individual police officer?
No, it is determined by a court.
And that can be applied to any object in a person's possession? By your own admission, that can be applied to most any item, even a flashlight.
If an item is being carried as a weapon, then it is being carried as a weapon. I'm not sure what your point is.
Oh my- what if a police officer decides you don't need a camera or cell phone on your person while walking past a jewelry store or bank?
In the UK the police have some discretion in the field. This can be abused, and then they have to answer for it. I don't see how else it could work. I'm sure US police are also trusted to make judgement calls.
Your specific example is fairly ludicrous. How is my camera a weapon?