Eric, you have some good points, and I totally agree that the RC is there for the benefit of the sailors. I make a point of stating that often at the events I run.
However, the school I am coming from is more conservative. Talking to competitors on the water is only OK if everyone has the opportunity to hear you (VHF or loadhailer), and normally, this is only OK between races, not during a race.
Matt and I are both certified ROs, some folks say we're pretty good. I can't speak for all of Matt's experience, but the ROs and judges who have been my primary mentors are Olympic-level, which could explain why I'm as conservative as I am.
I am unclear on what your last paragraph is saying. I don't know anyone that would protest someone for asking a question, at any level. I wouldn't answer the question as an RO, because the course would be properly posted, but I may point to the board at a club race.
Conduct of the RC at any race is somewhat subject to what the competitors want. But, unless you are intimately familiar with the sailors at the event, you have to be careful how much you lower the standards. There are plently of posts on this forum that speak to issues of perceived favoritism.
Mike