Lefty was somewhat of a mentor to me and I agree on the Bull. He was a natural at whatever he decided to do.Very gifted but also he devoted his life to flyfishing and writing. However there are two parts to fly fishing.
Casting: Yes go to the you tube videos and hopefully you find one that cast correctly. 90% do no. You can be a poor caster and still get the fly out there.Casting is a mathematical formula. Fishing is not!
Fishing: There are two types of fish, Smart ones and not so smart ones. If you just want to catch a few aggressive not so smart ones then it can be very easy. As posted above just smack the fly on the water 15 feet away and a bluegill will rush in to take almost any fly. Stock trout can be the same. We have plenty of stocking truck followers in Pa and they catch 20,30 or more trout in a afternoon. Are they good flyfishermen? No not in my eyes! I can take them on many different streams and lakes for fish such as wild brown trout and they will get skunked 99% of the time. It is all what you want and how much time and energy you want to put into it. I have taught flyfishing for 40 years and had many knowledgeable folks in my classes. Doctors,Lawyers and other very intelligent folks. One person Who commented after taking my class and fishing a few years said " Being a doctor was easy compared to learning to be a master on the water with a fly rod on waters I fish"