From: Rabbi Moshe Sofer
To: Rabbi Yisrael
The Chasam Sofer responds to his student's prior communication with a novel insight on Nazir 37: for R. Shimon, the principle that mixtures weaken a prohibition (requiring a full shiur) and the principle that permitted food combines with prohibited food to form that measure are logically inseparable, two sides of one coin. Therefore, any verse teaching that Nazirite prohibitions combine in mixture would automatically yield heter mitztaref le'issur, rendering mishras redundant, which forces mikol asher ye'aseh to be interpreted differently — that one must accept all Nazirite prohibitions — and resolves the difficulty raised against Tosfos as well as a question posed by the Shaar HaMelech.
Source: Shu"t Chasam Sofer YD §89