It is open to anyone to make a voluntary MOR report, if they consider the incident worth reporting. I think both of the incidents mentioned above would be useful reports. If an incident is MOR'ed it very often also gets reported in GASIL etc. too.
I remember when I was instructing on the R22 and the governor came in - we had lots of discussions about what was the best way to teach. I think we were pretty sure that the addition of the governor would reduce accidents when pilots were distracted from RRPM control going into confined areas, for example. However, we wanted to teach throttle-twisting during the PPL course, as we were sure it ought to be part of a pilot's tool bag.
Initially, there were two schools of thought:
1. You should leave the governor off for all/most of the dual flying, thereby giving the student lots of non-governor experience. Put the governor ON for solo flying to give that added degree of protection when the stude was off by himself.
2. Fly it generally with the governor ON, with some governor OFF training.
The POH changes more or less forced us down route 2. I don't do R22 training anymore (unfortunately), but I imagine that the amount of governor-off training will be much reduced now - at least partly because most R22 instructors will not be as familiar/comfortable as those who learnt without a governor.
However, I am not sure that this is quite the same as a governor being inadvertently left off/turned off. Pre and After take-off checks and a gentle lift into the hover are more likely to catch these, aren't they??