I am “over” teaching out of field in an unstable (who knows what the students will be like and what they will bring with them?), yet rigid (certain things must be covered because they must) program.
In a stable program, you can do it: take a standard curriculum and go.
In a flexible program, you can also do it: teach what you are comfortable with and that the students show interest in.
In an unstable, yet rigid program, the kinds of pirouettes needed can only be done if you are in field and have a full bag of tricks.