Thanks Nick, excellent explanation, I'm going to crib your notes for our instructors.
Standard oral question on the annual Canadian PPC ride (required per the guide): explain the difference between settling with power and VRS. I've noticed among new pilots it seems to be the new bogeyman, to the extent they are now being stupid on confined areas for fear of VRS.
To the OP's specific question on the 412, I've never encountered LTE or VRS in several thousand hours working bush with it, even tried unsuccessfully to induce it for demonstration when teaching type ratings. Must be there theoretically, but not something you're going to find flying good airmanship profiles. If you need a number, the 40/400 is plenty conservative.