But: Given the listening distance here, I struggle to imagine that he will get any razor sharp imaging/pinpointing... The distance between the listening position and the speakers is much larger than the distance between the speakers. I would assume that this will create a pleasant and somewhat diffuse soundfield, but not very precise pinpoint imaging. Now of course, given that Toole primarily seems to be a classical buff, that kind of soundfield is much closer to how music actually sounds in live classical concerts. And that could also explain why Toole always has been a fan of using reflections to increase spaciousness (but which may adversely affect sharp imaging). Whereas for me, I doubt that this kind of setup would satisfy me completely.
I agree that his front LR speakers are closer together than ideal, which would be the +-30 degrees in the ITU standard for Mch music. It is ideal for movies, too. That would also be the same as the equilateral triangle configuration often recommended for stereo. But, I suspect he might have set his closer together to keep them away from the corners and side walls. He could perhaps have compensated by bringing the sofa closer to them, but chose not to do so for whatever reason.
In my old room, the fronts in my 7.1 system were at about +-22 degrees. In my current room, they are at +-30. There might be more involved because of the room change, but I like the wider positions much better. That is for music as well as movies.
Reading the AVS web posting, though, the really curious thing is that he is looking to add speakers at +-60 degrees. I do not know what that is about, since it is not part of any discrete Mch format standard I know of, not ITU, DTS, Dolby, Auro, etc. as far as I am aware. So, those channels in the 60 degree positions would have to be artificially synthesized, not something I would consider. It does not appear he is talking about vertical angle, either. 60 degrees vertically is not part of any standard.
I know the aesthetics of the room are important, but I sure would have covered up 100% of that reflective tile floor with thick carpeting.
But, Dr. Toole and I share a keen appreciation for Mch music. I also greatly admire his Revels, which are used in a friend's Mch setup with excellent results.
Incidentally, on dialog articulation, my friend started with two Revel Salons, but he kept his old Piega center, a Swiss-made, ribbon-based speaker. The system was Dirac calibrated by me, but dialog articulation remained poor. He replaced the center with a matching horizontal Revel, just like Toole's. Dialog suddenly became much, much improved. Sometimes, it is just the speaker.
I hate to brag, but dialog articulation in my own Mch system with video sources is extraordinarily good. I am using the same Martin Logan Stage horizontal 'stat hybrid I have been using for the last 10 years. We do not use ear splitting sound levels. My wife gets uncomfortable if I do.