What if I hit post and then am like "Oh crap, I forgot to say something in there!!!"
I shoudl be able to edit the post to put what I forgot in.
Or maybe I forgot to proofread it, etc...
Or maybe a link I put in the post is screwed up for some reason.
I shouldn't have to make a whole new reply just to fix the link/correct my mistake/add a tought etc...
It's true that that's the reason there's a "preview" button, but I usually don't preview my messages.. I give them the once over with my eyes in the text box and then his "submit" heh.
As for post deletion, I don't see why it's turned off. For example, what if someone is bitching and makes a real ass of themselves. shouldn't they be able to delete the post and apologise.. or just delete the post and not say anything, hoping nobody saw it. This happens more often than you might think
Anyway, point being, own post modification good. own post deletion, probably a good idea.