What about going the other direction and developing a higher power amp (I guess 1200 is where some people are at)? Not so much for the added power/volume, but for added clean headroom?
For me there is a saturation point where more doesn't really much matter.
Assuming a reasonable stage volume for club work and FoH support for larger venues, I find 800 watts is more than enough.
I like ultra studio clean for some projects and my RB1001 (700 watts), MBF800, and 1500 watt pre / power rig all stay very clean. I really don't notice a difference in clean headroom despite a 2:1 margin.
I am not aware of any single cabinet that can handle anywhere close to this amount of power.
For that matter, my ancient SWR at approx. 500 watts gets the job done nicely for 90% of what I play too.
Since big power has become inexpensive, it is a great marketing factor.
Remember when a laptop with 5 GB was a huge deal?
Probably OK for many users but who wants more for just a few extra dollars?
.02