It also disallows the blockee following the blocker and blocks the blocker from seeing the blockees tweets. I think the reasoning is that if someone @'s your u

It also disallows the blockee following the blocker and blocks the blocker from seeing the blockees tweets. I think the reasoning is that if someone @'s your username, you can see it. If you block them, you can’t see their tweets and thus can’t see their @'s and won’t be bothered by them. If your tweets are not private and if blocking prevented a user from seeing your tweets, they could simply log out and see your tweets; therefore any coded functionality that would block them from seeing your tweets is useless. It's been like this for at least six months. It used to be you could tell that you had been blocked by getting an error when you try to expand a tweet, but now you can’t even tell that you have been blocked unless you try to follow the blocker.