I think the problem I now have with IT is that Terry is partially still doing the "spot-the-reference" thing, which gets old after one or two readings. The thing that frustrates me about this book is, I think that he tried to do too many different things and ends up doing none of them very well.
For example, there are themes--"civilization" vs. "barbarian", for example, that deserve more development than I think he gives. The Empire sees itself as the pinnacle of civilization, but, in fact, it is much more corrupt and vicious than the Barbarians. And these Barbarians, on the other hand, don't act in their typical Barbarian fashion (thanks to the instruction of the Teacher). They are more "civilized" innately--i.e. straight-forward and meaning what they say--than the Empire's type of civilization.
The whole concept of the Silver Horde has annoyed me ever since I first read this book. Granted Cohen and Teach are almost the only developed characters among the horde, but the idea that they can still defeat overwhelming forces BECAUSE THEY'VE LEARNED HOW THROUGH EXPERIENCE is pushing the concept of learning by experience farther than it can go. I don't find them funny--but rather a bit sad.
Terry seems to use "The Red Army" to allude both to the Chinese Terracotta Warriors
. He may also be drawing on Classical Mythology's legends of raising warriors from Dragon's Teeth. Rincewind certainly does not intend to activate the legendary Red Army (which seems to have very modern robotic elements) or to bring it to crush the people's oppressors. He's only trying to get away. And, he has no idea how to use them in an effective way, or even to get out of the one he's in. So, it turns out that there is indeed some truth to the legend of the Wizzard and the Red Army.
But the individuals who call themselves the Red Army, whose main actions seem to be their pasting up slogans (incredibly polite but not very effective), were to succeed in overthrowing the existing government, Terry makes it obvious they have no idea of what is needed or how to improve the lot of the people they are supposed to be helping. If they are (I think) a parody of the Red Guard of the Cultural Revolution, they are less than effective. After all--when Rincewind asks the farmer who's holding the water buffalo by a string what he'd like if things were to change, it's clear that these people have been so conditioned by their society (which uses something worse than whips) that neither the peasants nor their "liberators" have any idea how to make the country better.
My problem is that I think parts of this are marvellous--but when shoved into one book, it just doesn't work for me.