Though it's light on implementation, I hope this idea is useful. I
haven't actually implemented it, so I'll be interested to learn if
others see pitfalls.
I think the issue isn't dialup vs. broadband, it's simply speed of
rendering; even broadband connections can be slow at times. Therefore, I
wouldn't be inclined to do client detection -- I'd plan for all users to
get the same opt-out from the rich UI.
I don't have implementation details, but I know that it's possible to
render some text before the rest of the content. Yours could say
something like, "Loading too slow?
