I honestly don't know, it would be interesting to see the different solutions each effort produced.
For a bus I don't think anything special would be required, as the speeds are low you could just accept there will be tire scrubbing. I suspect turn radius is increased, but it's not like buses turn great anyway (could also decrease turn radius because of increased traction).
I think the racing world experimented with multi-wheel front in the 60's or 70's, and that tells me it was about traction for steering (tire tech back then was awful compared to today). I'm sure suspension engineers worked to ensure turn angle between lead and second wheel were optimized (and each axle probably had unique camber and caster control curves).
Check out the 60's bus in Magical Mystery Tour and how hard they turn that thing (skip to about the 2 minute mark). I think even a modern pusher would scrub a lot more and lean less than what that extra axle upfront enables (plus being front engine)..