Auto/Insta locking

I've played too many blind-pick games where someone immediately locks in without any regards for their teammates and ends up taking someone else's lane. For example, I recently played a game with this one guy who insta-locked as Wukong. We ignored him at first, but then somebody called jungle and Wukong says "I'm jungle." We told him he didn't call jungle so he wasn't going to be our jungle, then he said "I don't care, already locked in." Of course he was also a gold who did nothing to help and just stole kills non-stop, but that's irrelevant right now. What's relevant how how he immediately locked in the second champ select started. Something needs to be done about this. What I'm thinking is something like a timer at the beginning of champ select, and you can't lock in until a set amount of time passes. Maybe, like, 20 seconds or so. Does this sound like a good idea to anyone else?

Edit: Yes, I know you can't auto-lock in draft pick, what I'm talking about is Normal Blind-pick.