Mentoring is always a lot of fun, and quite rewarding for all parties involved. I think reefing is one of the areas where having a mentor could be tricky for various reasons.
There are so many ways to skin a cat in reefing, so many different views on what constitutes as right and wrong (QT vs no QT, cleaning sand vs not touching it, automation vs no automation, etc) that it would be hard to have mentorship in true sense of the word. Some people like to have everything handed to them on silver platter, while others like to ask question, research and try different things to see if they work. If you are to assign a mentor to someone, you would have to find a match in regards to thought process between 2 parties involved. You dont want to pair up someone who wants everything given to him/her with mentor that would expect person to do research and figure some things out for themselves. You also dont want to have someone mentor you who has completely opposite views on what works and what doesnt from your own, and doesnt allow you to try and fail. And that brings us to the question on how do you decide who should be a mentor in the 1st place. There are folks out there (not just reefing, in general) who have wealth of knowledge, but arent great in sharing them with others (just dont know how). There are folks out there that think they know it all, share all their info, but more often than not they are just plain wrong. You definitely dont want to have latter as mentor. If this is to be properly done, there should be some sort of vetting process to make sure proper mentors are selected. If anyone can just say hey I will mentor you, it can open up a can of worms and lead to lot of issues, and possibly monetary loss for mentee (is that even a word? lol)
For me personally, I like to read a lot, ask a lot of questions, sometimes stupid ones, get info from various sources, and then make up my own mind about how things should work and why. I wouldnt be able to work with someone who thinks their way is the best way and things have to be done certain way as an example.