The Custodians of Myth (3)
Those with larger frames had the advantage of storing more mass and energy in their bodies which translated to naturally higher durability and strength compared to their smaller counterparts. Hence, in general, size did matter in determining which party was going to be above the other before a fight even began.
That being said, those with tinier frames were not entirely powerless. The first reason was that during a fight, the bigger contender had to match the smaller opponent's height and movements which would usually make it hard to maintain proper posture and balance, causing them unable to utilize their full potential. Of course, this was a mere theory, and to realize it was a different matter altogether, only a skilled person could make use of this, like now...
"GgraAAHH!!"