What an excellent, fruitful discussion!

In my previous life I was always trying to get clearly defined requirements from my clients. Something like “Authentication process should take no more than N seconds”...
Amplification requirements in both cases clearly defined as follows:
M3 Sapphire - Compatible with solid state amplifier 8 watts and up into 4 Ohms
X5 - Compatible with solid state and tubed amplifiers 8 watts and up
To define speakers positioning requirements, we need the following parameters:
distance from the front wall (F),
distance between the speakers (X),
distance from the side wall (S),
listening distance (L),
toe-in angle (A),
anything else?
I was hoping we could come up with recommendations for both models: F ± ∆, X ± ∆, S ± ∆, L ± ∆, A ± ∆ (∆ can be different for each parameter)...
I don't use a 1-6 watt amp, I have a small-medium sized room (16x13), and practical considerations put me seven feet from the speakers so I went with the M3 Sapphire.
In my case, my listening area is part of a huge "great" room with 14 foot vaulted ceilings. I went with the X3 to fill the space plus I wanted the AMT driver. I listen almost entirely to classical from chamber to choral to full orchestra.
I have the X-5 and love them though I’m a bit closer to them at the seated position than is ideal. I believe that room size and sitting distance is a very important reason to choose one over the other.
In case there is no adequate mathematical model to get such recommendations, maybe we can gather the appropriate empirical data and still come up with clearly defined recommendations?

Otherwise, we have to “bug” Clayton each and every time...
