Thanks for the sound advice, however there is some contradiction in what you say if I understand you correctly. When you say "if you only practice for 30 minutes a day than all you'll be able to play is 30 minutes" isn't that an indication of how much one can play before he/she gets tired in a certain way? Also I don't know of any people playing woodwinds who can play professionally even with breaks for 8 hours (typical time for a professional musician in our country) and not to get tired. Aren't mouth muscles a form of human muscles after all? That's what my clarinet teacher told me and added that only good breath support could allow him to last 8 hours when his chops were already tired and he had to go through a 4 hour rehearsal after 4 hours of practice at home or vice versa. That was when he played professionally in a classical symphonic orchestra. If I've practiced woodwinds for no more than 1 to 1.5 hours a day I assume my limit is 1.5 hours until I start getting tired. That's what I could afford myself after work hours.