I've noticed that for the same pokemon at the same Power Up cost, the attacks of the XS pokemon are better than that of normal or XL.
Is there official data confirming/debunking this hypothesis?
Notice, that this is a different question to the one here. That question is focused on the size of the pokemon--and mentions that larger pokemon have higher health. My question here is then, do smaller pokemon have higher attack power? If there's no health benefit, then does this mean that there's an attack bonus?