Recently, I have had opportunities to ride a variety of plus tires and rims in a few different combinations. When riding narrower 35mm wide rims, 3.0 tires are definitely more rounded out than they would be with a 45 or 50mm wide rim, but I actually tend to prefer it. I can’t say definitively why it feels better to me, but I suspect that the flattening out of the center tread when run on wider rims feels less precise, harder to turn, and more sluggish to me. Now, with narrower rims, the peaked center tread feels more efficient and lively, quicker to turn, yet when I lean forward on the front 3.0 tire with lower pressure, it compresses, increasing tire surface contact, thereby yielding more front end traction and ultimately more control. I tend to acticely lean into the front when I steer and drift the rear more than I used to with previous setups and have grown to really appreciate the flexibility when I have that 29×3 Chupacabra at 12psi. Shifting weight fore or aft can really make a huge difference in how efficient the bike feels and how much traction the riders have at their disposal. Getting familiar with this sensation has made me faster. Undoubtedly faster.
Wide Tires on Narrow(er) Rims