Having just waded through all 14 odd pages of this thread I can understand Danny's frustration!
A few observations as a pilot experienced in both longhaul and shorthaul operations and having operated all over the world for the past 20 years.
ATC in many parts of the world is dire, most of Africa, South America to name but two. In the US we are constantly suprised at what we experience because, I believe, we think that because the controllers speak a type of English language that they operate to identical procedures and standards to the UK. A similar observation can be made when looking at many other aspects of life and behaviour in the US versus the UK!
I fly for BA and we constantly have a dilemma in the US when asked to maintain 180kts or greater to, say, 4 miles because we cannot then comply with our company SOPs of being fully configured and stabilised on the approach with approach power set and the speed within +20kts of our target speed. It could be argued that our criteria are conservative but it is plain from observing operations in the US over many years that we are fairly unique in having those criteria and also the system that monitors those parameters (and a lot else) namely SESMA. It does cause us regular problems in complying with US ATC instructions.
Operating into busy US airspace the often late and sometimes multiple (LAX in particular) runway changes give the impression of a completely fluid situation with no real organised plan of action for handling inbound aircraft. Similarly I have been vectored for miles around the surrounding countryside, when ATC are busy, when I cannot help compare with the UK procedure at London where, beyond a certain traffic levels, inbounds hold in one of four holding stacks and, having been descended in the stack, are fed neatly into the approach flow at the appropriate distance from other aircraft in the line.
Another observation. A few days ago at ORD, the usual three runways in use. I always get performance figures out of the system for all three runways because it is a guess, at best, which runway will be assigned for departure. We taxied for 09L. As we approached the 32L T10 intersection we were changed to that runway for departure and also told to contact 'clearance' for a re- route. We had a completely new re-route all the way to IAH and, having received it, returned to the tower frequency where the controller instructed us to line up. Now I can accept changes but to re-program the performance data (different flap setting too) and enter a new route (if only the first few way points) allowing the other pilot time to cross check this safety critical flight data takes more than 15 seconds. When I said we were going to be a couple of minutes the controller sounded exasperated and moved us across to the other side of the runway to hold clear of other departing traffic. It put us under terrific pressure (which I can deal with) but is a recipe for making significant errors. I question whether the controllers actually appreciate what they are asking us to do.
To balance the argument the US come into their own when helping aircraft route around weather. The difference being that they can see it on their radars whereas in the UK they filter it out!
It is a testament to the US controllers skill that they handle the volumes of traffic that they do without more serious incidents but I cannot help but feel that the system could be a great deal better. Regular famil flights for controllers would be a good start.