I had a couple of issues that I raised on the other thread before it went poof in the night.
Personally I'm against it - there is just something about it that I don't feel sits well with the open ethos of MN. However a trial is probably the fairest way to answer this, if there's strong feeling for it.
However coming off on debates on that thread about how it might possibly work, there were a few specifics that I was wondering about, particularly in relation to how Mumsnet already is.
1 - Would this, in theory, be tied to names or to email/IP addresses? If it's related to names then people can just change name whenever they want, and then they are unhidden again. If it's related to email/IP addresses, that seems very permanent, and also rather unfair if that person does have multiple personas on MN, and suddenly their very normal posts on gardening etc are hidden from other people
(I'm aware multiple personas is also seen as a bit of a no-no, but I suspect a large number of people do have their Chatty name and their Personal/Health Issues name etc.
2 - There was some very good suggestion that the number of posters you could hide was limited to 5 or so, which definitely seems to encourage people to not just hide hundreds of people they minorly disagree with. However, I don't see how that could work with name changes. You've blocked a name, that poster name changes, you've used "one of your 5" on a name that no longer posts, but how do you unpick that, figure out the new poster is the old poster, cancel one 'hide' and start a new one...?
3 - What happens if a poster changes their style and stops banging the drum that so annoys other posters? Say someone is rabidly anti-vac, offends lots of people by their one-track posts, and gets hidden by lots of posters. Then they eventually work out that this has happened and realise it was a mistake and change their posting style. But all these posters who blocked them, there's no way back, is there? They can't see that the poster has realised they were offending people and changed their style.
The last might not bother some people but it does bother me. Hiding posters, especially via email or IP address, is just so permanent.