If you put the person that really irritates you on ignore (thanks, as JZ mentioned), you can still see they posted. You may, as an irrational being, be driven to further rage, NOT KNOWING WHAT THEY ARE SAYING, BUT IT'S MORE NASTINESS...
The lead box should "not show" all forum postings by that user (rather than you are ignoring this user) , as well as "responding to user" in the header. It could skip to previous poster, maybe...
I mean, Baby Jesus, this is AMERICA, I want full blinders!