QUOTE "Is it really going to harm you wearing a high-vis - are you alergic perhaps? (im pretty sure your safer the more visible you are - is that not correct?)"
windswept, can you produce any evidence of pedestrians ever having been hit by a taxiing aircraft? Anywhere in the world? (This should not include anecdotes concerning pilots or ground crew walking into the rotating propellers of parked aircraft...).
The only concrete safety evidence concerning high-viz polyester tabards, centres about how dangerous they are in proximity to fuel bowsers as a result of the static electricity that they can generate. In this respect, high viz vests are extremely dangerous, and should really be outlawed from a H&S point of view.
As for more than two aircraft in the circuit being dangerous, I'll pass your comments on to Wycombe Air Park where there are regularly 4 aircraft in the fixed wing circuit, and sometimes as many as 7. In addition to that, the glider circuit may be active, as may the helicopters. Wycombe Tower seems to do a perfectly decent job of maintaining separation and I think that they might be a bit upset at your suggestion that what they are doing is by definition unsafe.
As for busy airfields where there is only air to ground radio or an information service, neither Wellesbourne (where there is an information service) nor White Waltham (which is air to ground) have a huge problem with airprox's or in flight collisions. Whereas, if memory serves, there was a recent incident concerning two aircraft at coventry?? (Sorry if I don't remember the details.)