It's true. There's not much smut in it. There's a fair amount of sex, but I tend to show only as much of that as is plot and/or character development, so once the conversation is over, as far as I'm concerned, so (usually) is the scene. (There are exceptions to that last point. Hammered has one reasonably graphic sex scene, and Whiskey & Water has... well, a fair number of fades at various points in the action, and I think one summarized sex scene (told mostly from the point of view of an old Victorian house, because I love my job) and two that at least get to the point of PIV before we break for commercial.
We have orgasm rationing in the industry since Jean Auel, so I try to go light on those. Her mid-period work triggered a shortage whose repercussions we are still understanding today.
None of those are particularly written to be erotic, though. And two of the three are--how shall I put this?--strictly business transactions. They come with a freight of angst and character and plot, but they're not by any means about the longing and the drowning and the two (three, twelve) hearts beating as one.
Carnival has one fade and two sex scenes, which are pretty much dispensed with in a couple of paragraphs (I actually get a kick out of writing sex scenes by indirection--the sort where you know exactly what's going on, but it's all implied rather than explicated; they're a lot of fun to write that way); A Companion to Wolves has some rather graphic, clinical, and (I hope) unsettling sex. (I think Sarah and I agreed that we were each going to claim the other one wrote the gang-bangs.)
The Stratford Man and The Journeyman Devil... well, there's a lot of sex in TSM. Some of it is erotic, some of it is cute, some of it is kind of horrific, and some of it, I hope, is a combination of (pick two) or (all three). Some is elided, some is explicated, some is sweet, some of it has an unmistakable resemblance to a dog returning to vomit. (Actually, I think one of the most erotic scenes is also of extremely dubious consent, and quite horrible once you look back on it later and realize what was going on. I'm pretty proud of that one, from a stunt writing perspective. Writing to the re-read! Yay!)
In TJD, there's only one sex scene. It's quite graphic, and it's rather terrible.
Undertow and One-Eyed Jack and the second two Jenny books are pretty much smut-free, by comparison. (The only place in Undertow where anybody gets any, I think it's dismissed with a sentence much like "And what with one thing and another, he stayed the night.")
Patience & Fortitude--I've written about fifty pages of it so far, and most of it is sex. Reasonably explicit and detailed sex. With, um, explosions. And magic. And magical explosions.
We'll see how much of it stays in for the last draft.
I think the art and the craft lie in writing what the story needs, what the narrative demands, rather than trying to meet some arbitrary standard of eroticism or humor or graphicness or lack of graphicness. If it impacts the story, it stays in.
Which is why there isn't really any graphic sex in Blood & Iron. Because nobody changes while they're in bed with anybody. And if nothing changes during a given scene, I see no reason to write it.