Byron,
First, of course, it depends on where you fish geographically.
If there are a lot of larger bass being caught where you fish, then you are likely to get your share.
It also depends even more on how often you fish. Finding your panfish fly in the mouth of a bass in the 3 pound class is mostly luck. The more you fish, the more likely it is that it will happen to you.
Another issue, of course, is where in a particular body of water you fish. Finding ‘spots’ on a given lake or reservoir that hold the larger fish will up our odds.
You just need to understand that using small flies is not the best way to catch larger bass. You will get a few, though.
Some little known ‘facts’ about largemouth bass fishing in general:
Most largemouth bass that survive from fry are genetically incapable of reaching three pounds. The vast majority live their entire lives as 1-1 1/2 pound fish. Bass over three pounds are rare in comparison to the entire population.
The ‘average’ size bass caught by anglers in the United States is right around 10-14 inches and about 1-1 1/2 pounds in weight. The factor of bass caught over that size differs from location to location, but in ANY body of water there are about 100 times as many bass caught UNDER 12 inches than over it.
Most anglers report the size of bass inaccurately. Overestimation of bass weight is normal. Often the ‘average’ 12-14 inch bass is reported as ‘two pounds’ by even experienced anglers. Using a scale or tape measure regularly will help you learn to correctly judge the size of bass.
I can’t count the number of tiems I’ve had fishermen in my boat that confidently stated that a fish was over 16 inches or weighed ‘three pounds’ only to find that with the scale in hand, these fish were ‘average’ fish that were under two pounds.
If you don’t have a scale and want an ‘easy’ conversion from length to weight it’s: Length cubed divided by 1600. (With this, you don’t have to spend the time to measure the girth, and it’s ‘close enough’ that many major tournament circuits use it).
Buddy