You nailed my interest point exactly: efficiency, size and weight, more friendly to the environment... also flexibility!
I could see a tri-mono design in a 1U chassis (which I think would be thinner than the 2200). Imagine amplification like that, for power users, and being able to juice 11-15 discrete channels in 4-5U of space.
(Yes, I am being silly, but, I think the point is valid.
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