Oh man. I'd think that a 7/10 on 20's would be damn near impossible to drive. Not saying it couldn't be done, though.
But I couldn't see me driving it a lot or even very far. Maybe I'm just getting old!
Along with the ride characteristics of a 30 series tire, (ouch!) I'd find that the lack of tight cornering would be frustrating.
Trying to power park it on cruise night? PITA!
Speed bumps? Even at 4/7, creeping over the monstrosities they build around here, I grit my teeth, & clench the butt cheeks!
But, it'd be one more reason to avoid the Walmart parking lot! Hehe!
Don't get me wrong. I'm not saying you shouldn't do this. Actually, I'd like to see it if you do do it!
I'm just an old guy. I've grown to like being comfortable! Maybe a bit lazy, too! Lol!
I've learned that if you push the limit, sooner or later you're gonna find it! (mis-spent youth! got scars! pain killers, too!) Even 6/8 is awful low! To me, anyhow.
Why not body drop it? Yea, a lot (a LOT!) of work! But you could get that lowww profile and still keep it static, with a decent frame height, & still run the 20's. 18's'd be better.
But even doing that, it'd still have the reduced turning radius. Fun on the highway, though!