This becomes about both personal style, and the tenor of the fields you are racing against. There's nothing wrong with it per se, but I would not personally even do false tempo at the front with a teammate up the road. IME when that does happen in a masters or P123 race, guys just go around the false tempo-er as if they were road furniture, so it doesn't gain your teammate anything.

Just existing near the front of the field with a teammate in the break has an effect on the field. Chasing attacks, sitting in if a group gets clear, and pulling through immediately if you get to the front has a similar effect. It's demoralizing for chasers without requiring active dickery on your part.