Hello Scott. It is so good to hear from you again! I really missed your departure from the last place we hung out together.
And thanks for the kind words regarding ASR Forum. That is what we strive for and good to see that it shows.
Yes, Kevin is a very good friend and he and I have talked a number of times about this. My sense is that like other professionals you mention, through so much exposure trying to hear speaker sound itself, may have evolved his hearing to be much more sensitive than the rest of when it comes to reflections.
BTW, there was follow up research on Dr. Toole's hunch regarding mixing and mastering engineers in a rather recent AES paper
The Practical Effects of Lateral Energy in Critical Listening Environments, this very thing was tested in controlled environment to determine preference for diffusion, absorption or doing nothing (reflections). Here is the test subjects the outcome:
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As you see, it turns out the majority of these professionals actually side reflections than not.
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As you say, the panel speakers have a sound that when combined with right music, is a very unique experience.
Hope we see you more here.