If you can format your posts, but are not able to see that formatting, you might just have to edit it 15 times. Would it not be better on the server if someone could preview the post and fix errors before it goes to the server? (Previews only require RAM reads and writes, while publish requires hdd writes...

That could be useful, I think.

Ooh, that's a good suggestion! I'll put it down and see where I can fit this into my schedule