I am a new poster on Mumsnet, but have been reading it fairly regularly for the last few months.
It strikes me as odd that a poster can't edit her post for spelling and grammar once the comment has gone live. Wouldn't an edit function save the hassle of writing 'corrections' posts and relieve the anxiety that I some posters have in thinking others will think them illiterate if there's a typo or a misplaced apostrophe in their post?