There's nothing to debug. We know why OS X is slow on Dolphin. OS X has slow (and outdated) OpenGL support with little indication that Apple will fix it.
Over the years the OpenGL backend has changed to become more accurate. Without modern extensions and a reasonable driver, performance suffers. Considering OS X counts for about 5-6% of our user base, it didn't make sense to hold back Dolphin from becoming better just so that crappy drivers that can be worked around with dual booting doesn't slow down.
I'm sorry you don't like that answer, but it is what it is. Nobody said you *can't* use older versions. We just won't really care when things are buggy in those older versions as we only support the latest stable on the forums.
Over the years the OpenGL backend has changed to become more accurate. Without modern extensions and a reasonable driver, performance suffers. Considering OS X counts for about 5-6% of our user base, it didn't make sense to hold back Dolphin from becoming better just so that crappy drivers that can be worked around with dual booting doesn't slow down.
I'm sorry you don't like that answer, but it is what it is. Nobody said you *can't* use older versions. We just won't really care when things are buggy in those older versions as we only support the latest stable on the forums.