« on: January 08, 2011, 10:21:31 AM »
I would expect #2 to attenuate more than #1. Mash temp (and grist composition) makes far more difference than the attenuation rating of the yeast. That's just a way of comparing one yeast to another given a standard wort.
+1 I've brewed beers that had 80% attenuation with a yeast that was rated for 74% tops. Low mash temp, plenty of yeast and a moderate and controlled ferm temp all work to get maximal attenuation.