Looking at the graphs a bit harder here, it seems that the average voltage is around 3.6v/cell. Wouldn't this indicate that running them at 20C is not the max continuous rating, and that they could be pushed quite a bit harder? But at the bottom of the 3.2a/h cell graph it shows 12a/h on the discharge?
edit: my eyes hurt, I will wait for you to enlarge them before I try to read any more