Okay, last tip. Sometimes I will have a lot of builders who simply refuse to stay on their task or only examine the huts rather than fixing them. When this happens, I do a concentrated group training.
I take every builder that's giving me problems to the hospital. No other villagers are allowed there. And then I make them fix and fix and fix AND fix until they've gone around 10 rounds or 5-10 minutes (depending on my own focus!). NO villager may leave until they leave to fix another hut. If they want to leave for any other reason, it's Hotel California for them. They keep fixing and fixing and fixing until they finally get the hint.
I have found this to help. I suspect it has something to do with their skill levels. Or maybe there's some kind of mathematical calculation based on their rate of success which means forcing multiple successes adds to that calculation. I really don't know.
I do know that a villager who has been forced to do a skill too long will be more and more stubborn about doing something other than that skill. It's like they HAVE to eat or take a break. So I let them. If you watch, they'll frequently come back to their skill after their break.
Okay, so that's the long — errr... VERY LONG — explanation of the strategy I use. Take what works for you and leave the rest, modifying it to whatever works for you. I'm sure there are many other methods of training villagers to reach the EE level.
I think if there is any key to this, it is to not get too fussy about keeping your villagers on task. Let them have breaks. Just watch their overall progress. And when you find a villager that's lagging behind, then find a way to recognize that villager from a group so you can redirect them more often (or do a concentrated training session as I described above). I have found that most villagers will master in their skills even with all their breaks.
Did anyone actually read all that?

I hope someone finds something in all of this to be helpful.
