Is that weird? I feel like it’s plausible though. Very rare to have chess games with more than 200 moves.

Yeah I kind of thought that it meant "you can get to any valid position in 218 moves max", it was hard to parse.

It’s also rare to have one with more than 50 moves. I’m curious if this class of observation will help establish a true bounds. Especially because we don’t have a definition of what it means - my instinct is to first do that, so “infinity” isn’t the obvious upper bound.