you can ignore posts from anyone you want without the ignore list
It's pretty hard to do sometimes, if we are to be honest, especially if the person follows you around the board, posts in your thread, addresses your posts, says nasty things about you, tries to sway other people's opinions of you (or ruin your reputation with others), etc. There are sickos out there, you know!
There are also posters who deserve nothing more than the ignore function because they contribute little or nothing to making the forum a good place to post.