Thanks, Bander!
I’ll have no problems with HTML buttons on my personal installation, but the one I am working on for work is a different ballgame. Ultimately, there are likely to be at least 50 or so members with publishing privileges on various weblogs and, given everything, I think it’s going to be best to stick with ‘safe’ HTML and a few formatting buttons. I’ve got the defaults as I want them and I’ll just have to hope that no-one edits them! At some point, I will probably create a private weblog just for site publishers, with a few hints, and hope that they read them. I probably sound like a bit of a control freak but my main concern is that the output remains valid, accessible and in keeping with what is already there (or, rather, what will be there one day in the distant future). I’m still very new to EE, and am still exploring the possibilities.
which actually shouldn’t be *too* terribly difficult, if you’re halfway technical
Ha - I’m nowhere near halfway technical, unfortunately! I took a look at the file and it frightened me silly - rather you than me on this one, I think 
Did you manage to ban yourself?