how about a 4 on, 4 off rotation
That wouldn't work with an instructor course
Make it attractive
That costs money, and schools will not pay
Can you really see an Offshore/VIP/HEMS captain taking a 50-70% pay cut to go teach in an R22? (answer: no)
And most Offshore/VIP/HEMS captains do not hold an instructor rating, nor do they have any instructional experience.