You are jumping to conclusions. I merely stated the FACTS, which are OBJECTIVE measurement.
When you stated this,
“I guess some of us are interested to see if these $30,000 speakers can finally have on-axis and off-axis FR that are better than $300 Infinity P363 that cost 100 times less.” I assumed you felt that it was such an important aspect that that alone would make the Infinity’s better designed hence a better sounding, more capable speaker. If not, why even bring it up - what’s the point of dwelling on that?
Do we buy speakers to post their graphs on the wall or to revel in their reproductive capabilities? I chose the latter.
Of course, I would take the 800 series over the P363.
Just like I would take a Lexus, BMW, Mercedes over a Hyundai. But if the Hyundai had better objective measurement (interior noise, braking distance, acceleration, etc.), it would still bother me.
That implies that you would “take” them for status and luxury, not performance. I wouldn’t.
I don’t really see a correlation with your analogy. Either way, it wouldn’t bother me one bit if the Hyundai excelled in some measurements especially if as a whole it gave me a horrible driving experience compared to the “Lexus, BMW, Mercedes”.
I see no reason why other companies (Revel, KEF, TAD, RBH, Salk/Phil, NHT, Ascend, etc.) can make great sounding speakers that have great on-axis and off-axis FR, but B&W is incapable.
It still doesn’t matter because those brands sound just as different from each other as they do from the 800 Series. I like some of the brands you mention and am not a fan of others. Their on/off axis measurements did not change my opinion.
As for B&W being “incapable”, I highly doubt that. I'm sure you misspoke. I'd say it's more of a choice on their part.
The original B&W 800 Matrix had no problem sounding great with good on-axis and off-axis FR. I would like to see B&W go back to their 800 Matrix roots.
Who knows, maybe they're on to something over there at SRE and there’s good reason why they don’t anymore. While the Matrix sounded great, I’m with Dr. Waldrep (and many others) on this one, The 800 D series is much, much better.
Easy to prove? How is it easy to prove when it's not even easy to find two speakers with "near identical perfect measurements?" I get the impression you're still hung up on the idea that speaker measurements consist only of on-axis frequency response, +/- x dB. As explained above, you have to look at off-axis frequency response as well. And different speakers, even with similar on-axis response, often differ wildly in their off-axis response. Then there are other measurements - waterfall, THD, IMD, linearity vs amplitude, etc.
The fact is, there are no speakers with perfect measurements, or anywhere near that. And different designs have different measurements. Once you understand the measurements, a more complete set of them can give a pretty good indication of how a speaker will sound.
I’m not hung up on anything related to speaker measurements. Far from it.
You’re actually making my point for me in a roundabout way. Isn’t it a bit like Whack-A-Mole? One can knock this speakers off-axis FR, that speakers disturbing waterfall and goodness have you seen the THD on those over there! Where does it end? None of these measurements individually will tell you how a speaker will sound. If it were that easy all of the guys that adhere and demand the best measuring speakers would all own the same speakers wouldn’t they?
I always trust my ears to tell me what I'm hearing. If you have a moment, read through this brief thread (you can start on post #9).
http://forums.audioholics.com/forums/threads/plugging-ported-speakers-what-does-the-amp-see.104189/
EDIT: ha-sorry, I just realized you were in that thread.
It may be true in many cases that “Once you understand the measurements, a more complete set of them can give a pretty good indication of how a speaker will sound” but IMO another thing that can give you an even better indication of how a speaker will sound is actually listening to them.
But what do I know, after all I'm less than (<) an ear giant.

Peace everyone, I'm going to go sit in the sweet spot and marvel as the 805D's remove that pane of glass!