I started to wonder this most as I got towards the end of Raising Steam, when the stakes are high and the action kicks in, but just wasn't feeling that in the way that you probably should. I was still enjoying it, still turning the pages and smiling, but there's no drive and urgency in it, no edge. Its a strange feeling to get in a book which is trying to have so much going on, but in the end I think the big problem is we've seen all this before.
So this time, the Steam Train comes to the Discworld. Right from the start we've been here before; the Discworld, a realm of mutable possibility, has reached the right moment for the emergence of the the Railway, and so, practically overnight, the trappings of the Steam Age emerge, Athena-like, across the Sto Plans. I have all sorts of problems with this. For a start it's one thing to have say, the birth of Cinema be driven by an ancient magical curse that opens to door to powerful entities beyond space and time, but here there isn't anything behind the Steam Engine other than some sort of memetic injection into the world. The idea that the trains themselves could be alive is toyed with but never developed but you're left instead with the myth of the heroic inventor changing the world.
Here decades of technological progress are accelerated into a very short space of time, with Inventor Dick Simnels genius bypassing all the concerns that vexed the birth of the railways first time out. I know it's a fantasy novel, and I know it's allowed to take liberties with this sort of thing, but its progress at so little cost its...well, its slightly weird. Even the scale of the construction of the rail lines is uniformly positive; the workers are all paid well, and given houses, and the only Railway Baron character - Harry King - is a benign, fatherly figure. The Railway - and by extension all the industrialization that goes with it - is good, and never a Dark Satanic Mill in sight.
The villians instead are the forces of reaction and conservatism. Now in fairness I'm pretty on board with this, but it's also clumsily done. In a follow-up to the plot of Thud, the Grags, arch-religious Dwarves are determined to roll back the clock and destroy any forces of modernity interacting with their people. As much as the Railway is Good, the Grags are Bad, portrayed as murderous hypocrites or simple, cowed dupes. This simplicity - technology as progress, religion as reaction - robs the book of any real teeth. There is no sense of the land and lives destroyed by the rise of the Railways, and no sense that maybe, just maybe, the sort of cultural homogeneity spreading across the Discworld could be anything but good. But thanks to the train, you can travel anywhere, and its all the same. I'm not sure how I feel about that as a message.
Look, Raising Steam is fine. I enjoy it, for what it was. It's got some good jokes, and its nice to spend time with the characters, although Dick Simnel aside I know them all already. It's a comfort blanket of a novel, warm and just sort of nice, and there is a place for that on my bookshelf and always will be. After 40 novels, it's wrong of me, I think, to expect to be challenged or surprised by an author, and I guess I've made my peace with that.