I've known some smart elders, but like just about anybody on earth, they were smart on some things but dumb on other things. Of course, we were all dumb to accept the nonsense that the JW religion expected us to believe, and the absurd direction we blindly followed.
Some posters above have made some great points RE: born-in elders vs. converts. I was not a born-in, but I came in as a teen. I found that the born-in elders were much more likely to think of spirituality as equating to compliance at all costs, whereas the non-born-ins were more likely to emphasize spirituality as the ability to perceive Jehovah's thinking and make decisions based on principles rather than rigid rules. Born-ins always needed to consult a publication or someone with higher status before doing ANYTHING about ANYTHING.
In my congregation, most elders were born in and that is probably why I was never appointed as an elder myself. Sure, they liked me and had glowing things to say about me, but they were hesitant to appoint someone who thought too much outside of the box, questioned things, disagreed with things, and didn't pretend to be happy when he was having a rough time.
Unfortunately, all that "humility" wound up rubbing off on me in certain notable ways. One particular time, I asked an elder a question about grooming, to see what his opinion was before I made a change to my hairstyle. Not because I thought anything I was doing was wrong, but because it's often times extremely difficult for someone who is not born in to figure out what the congregation around you will find offensive. It seems that born-ins all have this innate sense about what all the unwritten rules are. Those who weren't raised in the religion, even if they've been in it for a decade or more, just have to tip-toe around the minefield of perpetual offense-taking by the born-ins.