> And what is your evidence?

Hands-on experiment and comparsions, and conversations with people
doing active research in schedulers and real-time work.  Discussion
with experts in mpeg decoders for non-Unix systems.  Seminars by
former PhD students here who've now moved on.  Some of this stuff isnt
published yet, so if you want more details, I'll have to ask.
Maybe we can arrange a demo.