I have run in to problems sharing a pitot between ASI and Cambridge
302, resulting in several very frustrating days at Hobbs one year where
it seemed as if I had forgotten to thermal. Separate pitots for the two
instruments solved the problem. Luckily, I have a tail pitot and a nose
pitot so each can have its own. The 302 seems particularly fussy about
having its own pitot and static sources however.

John Cochrane