Ugh, I don't know, a lot of things could skew that result, from font/button sizes (it's hard to miss if you could only fit 5 lines of text on your screen) to insane shortcuts to memorize (I mean c'mon, ⌘-⇧-4 to take a screenshot? There's a line or two about that at the link, but it's presented like inferior and ambiguous combinations are the only one that UI/UX folks can come up with) to ergonomics of the input devices themselves (some cannot stand chiclet keyboards, some can be really productive with trackpoints—sure, this doesn't sound anything like pre-1989 Apple but you get the idea) to even cursor speed/acceleration curve settings. That being said, I'd like to see some details on that R&D.

I still think this might hold true. But for me mouse (and touchpads, trackpoints) trigger repetitive stress syndrome - so acme isn't really an alternative - yet.

But I have some hope for merging the ideas of acme with proper touch screens/digitizers.

Also, the poor experimental design and lack of peer review about casts some doubt, really.