I don't think that he is an animagus, let alone a pheinox. If snape was Fawkes, wouldn't he be extremely old? Animaguses cannot be reborn. Remember in the 2nd book when Harry was in dumbledores office and Fawkes burst into flames and was reborn again? Snape wouldn't have been able to do that. Also, are you trying to say that voldemorts and Harrys wands are brothers because they both share snapes tail feather? There is no proof that snape is Fawkes. (btw I totally understand what you are saying, and I'm not trying to be snotty,)