I was out bass fishing last night and got stopped by another fisherman. I had seen him a few times at the lake. He uses small flies roughly 1/4 of the size I throw. The basic conversation was they 'why do you throw stuff so big?'
I went into the whole bigger flies catch bigger fish theory. But its more than that. My fishing has proven that bigger flies catch bigger average fish. They also catch less fish, cause the little ones tend to leave it alone. So its really a decisions by the fisherman. Do you want 10 one pound fish or one 10 pound fish. Really comes down to that. Every time you hook a little fish you have wasted a cast that potentially could have hit a big fish, but you also risk spooking a larger fish in the area.
Last night I only caught one nice bass. Probably 4 pounds. He caught a dozen 1 pound fish.