You are asking me to disprove a negative of sorts, you are asking me to prove something wrong that is not provably wrong because there is no falsifiable standard. You made an assertion that Paul is the "most Jewish" because he claims to have studied under Gamaliel as a basis of your point regarding why the Law is not binding to Christians. It is you who must back up the claim that studying under Gamaliel makes Paul "more Jewish", it is not my job to justify the idea of Gamaliel being wrong, it is you who must justify that being under a revered Pharisaical teacher makes one "more Jewish" and then you must justify how that position bolsters whatever it is you are trying to claim about Paul.
As far as I'm concerned, there's a decent reason to believe that Simon the Zealot, what little we know about him, was the Most Jewish of all.