No way would I hand my account over to anyone. That's just asking for trouble. I'd be surprised if it wasn't against some rule or another too.
Being new to the clan thing, I'm still not sure how I feel about it.
Apparently the was a recent purge of idiots and non players so that may explain why my experience has been mostly positive so far.
It's nice to be able to platoon if I want, but I quit feeling like I HAD to platoon up if invited pretty quickly. Most of my Clan platooning exp has been good.
I only ran into one idiot. He kept choosing tanks 3-4 tiers below what was was being run and was trying to give crappy advice. Maybe he saw that I don't have a heavy and assumed I was a noob or something. Or maybe he's a 12yo and normal.

(it wasn't Cat0020. He's fun to platoon with.

)
Tank companies look like they could be fun if you have an experience and good commander. So far I've only been in one, and the commander kept wanting to "try something". We lost every battle. Maybe next time.
So far the clan I'm in seems pretty laid back. The goal is to join Clan wars, but there doesn't seem to be any pressure. They are going to join a tourney, but when I let them know I didn't have any tanks in the correct tier, it was no big deal.