No idea if it was the left or the right.
I think even if the manufacturer indicated the handedness (would "chirality" be the appropriate word to use here?), we would need measurements to show which angle provides the most even response. Trust but verify, after all.
Yeah, head in a vice thing is what I was talking about, though the uneven left/right radiation would have definite consequences for spatial qualities. I couldn't say what those would be in advance. Likely the biggest issue would be difficult setup.
The rest of the procedure is as you said, including the fact that the further away you sit, the more the room is involved. At this point, when you start building the stereo setup, you start judging the room/speaker/listener interaction rather than just speaker itself.