hmm... since both you and [MENTION=426321]Chombi1[/MENTION] gave the same answer, I'm going to assume that someone has actually tried it.

In a more practical sense, I do think it's an oversight in marketing to not have a visual cue to the wonders that lie inside the shell. A BB cutout would be a necessity to get the full value of this unique axle. Of course, you've got to leave the sleeve out, so you'll be cleaning it frequently.
With a Phil BB, you can see the splined retaining ring.... although no one knows if you've got the steel or titanium axle.
Wiith the Campy SR titanium axle, there was a version with a threaded stud on the end, which means that it is visible externally (because you won't install the heavy dustcaps after paying for the full SR group). Maplewood bike shop in the St Louis area has a Raleigh Team on display with just this arrangement.....



I think this was the first time I've seen this type of axle in person.

Steve in Peoria