A good rant, Shed, and with some justification..........BUT, the fact is that some airports have made no attempts or appear to be uninterested in making passenger experience better. It is never going to be perfect, we all understand that.
In relation to bjones4 lens problem you have to ask why only Manchester T3. If camera lenses are repeatedly showing up there as pots of gel they should be aware that there is something wrong with their x-ray equipment or its interpretation and they should be doing something about it. Fixing the problem. The rest of his experience after security was every bit as bad as my own that I commented on further up this thread.
Some airports have made really good progress, LGW has improved beyond belief (now if only they could do something with their dreadful free Wi-Fi but we can live with that problem).
The most improved airport experience in my travels is Dublin T1. I used to hate going through their disaster area of Security with over-bossy staff. The worst at the time. You even had to queue to get onto the Security Queue proper. Mostly only 3 or 4 lanes open out of 12 and regular queue times of up to an hour. They made the effort and over a period of time have succeeded in making Security almost "enjoyable". Over the past two years the most I've ever had to wait is about 10 minutes (including at peaks) and everything keeps moving. The staff were either retrained or replaced and are a pleasure to deal with. Someone at MAN should send a team over there to learn a few lessons.