Sub-pixel is set to OFF by default because with universal settings, the highlights become far too dull (they get clamped before tonemapping). Reason why most people didn't mind, is that until recently, IR+LC was very dominant method,
and with common approach to setting subdivs manually high, you could force a lot of subdivs to go as secondary into material, and that would retain some highlights.
The bias is pretty strong, and you can't retrieve local highlights back in post (outside of manually painting them), because there is no information from which to extract, it's clamped. You can just rise highlights overall.
But I too used this often, pretty much by default on every animation :- ) Perfect AA, great speedup too.