Re: Sensei -- drinking??
Your instructor drinking before class and coming to class "wobbley" (for whatever reason) is an issue. It's hard to advise you without being intimate with the situation. That being said if you are friendly with sensei outside of the dojo then talk to him about what you're observing and how it's affecting you. If he interprets that as an advance then you, IMHO, should find another teacher. If you have a strict teacher/student relationship then (I'm sure I'll go down in flames for saying this:-)you should say nothing. If you are concerned for your safety then "step back" and wait to see what he does....other than that it is not your place to say anything.....