I can't speak for the person you're commenting on - that is, I have no idea what the 'Hm' meant. Also, I don't think it's generally discouraged. Lots of people write raw HTML (in some contexts).<p>But <i>I</i> certainly wouldn't want to write an entire book in HTML - it forces you to type a <i>lot</i> of brackets and tags. I'm sure your editor could take a lot of work off your shoulders, but even at that you end up typing a ton of macros (I would think). In any case, it seems easier to me to type the bulk of it in Markdown (or the like) and only occasionally drop down to raw HTML. To each, his or her own though.