Well imo asking if size matters is like asking if a person has a faster punch does it matter. Or if someones legs are longer that yours does it matter. In all actuality size is just another persons advantage or disadvantage. In asking does it matter id say yes to an extent but, is it a deciding advantage i'd have to say no. It's just one variable in a long list of advantages and disadvantages. IN short the person with the most advantages will win weather he's bigger or smaller.