Hi mstrawmyer
We only had this issue on IE6, and as you rightly say its only in the IE loader that this file exists. In tests Firefox for us has always been ultra fast, but most of our users use IE6, or IE5.5. Interesting how your experience seems to be similar as ours, I thought I was going doo laaly tat being the only one with this problem.
My gut feeling is that load.ashx is a bottle neck as its being called loads of times to load scripts, images etc. If for some reason .NET slows down this is used so much its a possible crunch point. I can see why they are using it as it makes coding a lot easier just changing some params, but it is an overhead as far as downloading files is concerned, IIS could download them much more efficiently without getting .NET involved.
When you make it hang in Visual studio whats the memory and CPU usage like?
Is anything on the machine busy?
Can you press the pause button in VS? Where does it take you too?
Anyway thanks Adam for the latest update, dont forget to update your change log, looks like some other files were changed as well as IE loader.
cheers