Before I was born my parents bought mezuzos from a sofer. Shortly afterwards my mother was at a shiur for ladies given by this sofer and he said some things that were so strange that she decided she didn’t trust him and went to get them checked by a third party. Sure enough they were typed.
twisted: Traditional yemenite sofrim write on g’vil (pronounced Djah-wil by yemenites and some diqduq freaks) which is very soft and pliable. An ashkenazi sofer I know writes g’vil mezuzos for the reason you mentioned.