IE users should already be used to lack of rounded corners, full page reloads for address changes, and more things as IE's release policy causes it to fall further behind the web. Not letting them do something else won't change their already poor experience.
IE and Safari (Vast majority of desktop computers and a good chunk of macs and IOS devices) don't...
...In fact, I have just re-read your original comment and noticed the "various parties" bit which my brain skipped over before.
My previous belief was that you were saying they should just switch the site to SPDY right now and screw anyone who doesn't support it right this moment which is obviously unworkable.
But since that doesn7t appear to be the case, i have no idea why downvotes were done (unless they made the same mistake I did).
If you want 100% support; just wait for the IETF to finish HTTP/2.0. It may not be the exact SPDY protocol, but it will most likely support a reasonable form of multiplexing, and I am confident all major browsers will implement it. But its probably ~2yrs away.
Similar Technique...Like what?
Downvotes were probably due to those two things "Not really providing a useful answer" (sorry if that comment offends. Just my opinion).