Is the block feature broken?

I've had to block a few people and it seems to me that the feature isn't working properly.

I am still able to see the blocked person's messages in every chat except for /whisper. I am still able to receive mail from them. They can still invite me to their group or request to join my group.

I am hoping (and wondering if) it is supposed to do more than just prevent them from whispering you.