A long time ago a very wise man gave me a bit of advise that seems to applie to many occasions. And I quote, "If you and me was exactly alike, there'd be no need for one of us." Point being you need to decide for yourself. If you will advance quicker by watching your back cast, if it will help you become more confident, comfortable and able with a fly rod, whats the harm and who's to say. Personaly I instruct my students to observe their efforts in all directions. Seeing is beliveing, and understanding. OK actualy I put it a different way. If you can only see half of what your doing, then your guessing at the other half. Its going to take you twice as long to learn. This of course means your learning half as fast, which may turn you into a half-fast-caster.
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Captn. Paul Darby
Capt. Paul Darby Dont wait to be ask, get out and teach.