About the dual-core "function"...

[The Phoenix]

Well yes & no, the media engine was only used in Async audio mode, and was extremely unstable when run on there, that's why only a few ran successfully on there like Turok Dinosaur Hunter, which relied on a Async bug most of the time, and ran way too fast, because of it.
Sadly the Media Engine coding was never attempted again, because of there being no way to debug it.
So no improvements were ever made, unless they are working on it now, as I type this, I hope so.