I am a self taught bass player that has been taking lessons and it has helped me immensely. Things like flying fingers have improve quite a bit. My main teacher is a professional rock musician who has not taught before. I decided to try out a person that was classically trained and 3 times the price. He pointed out something to me. Although I DO alternate my fingers, its isnt perfect. Sometimes I will use my index twice in a row. He says that needs to be fixed. My rock teacher has not mentioned anything. What does everyone think? Does it affect the sound at all?