Heck yeah! I'm most recently coming from 285/65/r18 Falkens and didn't bother checking the difference. I'm at 11.6mpg uphill with (3) people and ski gear. 14mpg downhill by myself.
I think the steering feel is definitely lighter that a wider tire. Feels super nimble. I felt that very much with my old V8 4Runner too (had 255/75r17s KO2s and 255/80r17s Falken Wildpeaks).
Good point on the KDSS rub with the Mickey Thompson sidewall bling factor.
As far as your stealing my 35" thunder goes!!!

I've always been confused on this--my understanding based on actual vs labeled measurements is that a nominal/published 35" tire is anywhere from 34.1" to 35". Same for a 34" tire (a "34" is anywhere from 33.1 to 34). Etc.
Here are some snips from the Mickey Thompson website, still not sure where that leaves us!
Note the "35x10" listed under equivalent size in this first snip.
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Note the "OD IN" size in this second snip
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