Hmm. You know, I was thinking about the A10's big.LITTLE-style setup recently, and wonder if this might be a symptom of switching to that kind of design. In benchmarks, the A10 will fire up the powerful cores and score very well, but on smaller tasks that only use the "little" cores, I wonder if you might actually see stuff like this, where the slower cores aren't as fast as a 6S?
EDIT: I think the CSR2 result here might back me up - when first launching it's a bit slower, but once the game loads in and starts demanding performance the 7 pulls ahead.