I think we were both thinking backwards here, I just remembered that movement speed is inverted.
The lower movement speed is, the faster you go.
So max(speed, 200); while indeed setting a *minimum* limit on the value; sets a *maximum* limit on the actual observed speed, and 200 is actually rather slow iirc. The default is 150 or so. Speed pot greatly *decreases* your speed, setting it to something like 70 or 80, which is lower than 200; and thus the higher value (200) would get picked.
So speed pot should have no effect.
Man we were both right, I was just thinking backwards.