I've not enjoyed every Turtledove novel I've ever read, but I'd never seen one that was so badly written and falsely advertised that I felt I'd been conned out of the money I spent on it. The Grapple came closest, but I got that for free by winning a contest. (The one time I win a contest, and the prize is The Grapple.) But no, I'd never felt conned out of money by Turtledove.
I can't say that anymore.
The Grapple was bad in comparison with other TL-191 and Turtledove novels. The Golden Shrine, however, was so hackneyed that far, far worse authors, like David Hagberg or Robert Conroy, would be ashamed to put their name to it. And unlike The Grapple, TGS is the finale of the series, so the shadow of its failure falls heavily across its two prequels.
The book pretty much chucks the established themes of the first two novels and reveals that the story has always been driven by a prophecy that everyone's forgotten to mention till now. Marcovefa appears to be the prophet, but the Rulers know the prophecy too, and it's why they keep sending assassins after Hamnet. (Which they'd been doing since before Marcovefa was introduced.) The prophecy is that Hamnet will prove to be the Rulers' most dangerous enemy. Details are added in, but they're wildly inconsistent, changing as the plot requires them to. I have to think Turtledove used them to foreshadow scenes he'd thought of but hadn't written yet. When he wrote them he realized they didn't work as he'd planned and changed things around, but didn't bother going back to fix the prophecies. This could all be explained as the characters having an imperfect understanding of the prophecy, but instead no one seems to notice it keeps changing.
Probably because they too change as the plot requires them to. The most interesting characters from the first two books, who need the least character development, get bogged down with non sequitir new character traits. The flat characters stay static as ever, including Hamnet--except now he's a whiny, juvenile thrower of hissy-fits, too.
And all the characters contradict their established actions and personalities, sometimes several times on one page.
Back to the prophecy, though. It hints that each of the main characters will play a vital role in defeating the Rulers and finding the Shrine (or rather, finding the Shrine and defeating the Rulers) but in the end most of them were just along for the ride. Only Marcovefa and Hamnet live up to their prophesied roles: Marcovefa by casting the spell that destroys the Rulers and uncovers the Shrine, Hamnet by enabling her to do so by--I can't believe I have to say this--having sex with her while she's in a Ruler-magic-induced coma to wake her up. THAT'S what makes him so special!
The Shrine didn't feature in the defeat of the Rulers. (Neither does Hamnet's plan to release a female Ruler prisoner to go back to Rulerland and touch off a feminist rebellion against the misogynistic men; apparently she first decided to research what happened to bit players who led rebellions in Turtledove novels, and died of old age waiting for something to come of the many rebellions in the Settling Accounts novels.) Our heroes do find the Shrine right after--it's too busy being hokey to answer questions--and a high priestess says she's been with them, guiding their fates unnoticed, all along, like the Borg Queen saying she was at Wolf 359 after the fact. She gives Hamnet a message for Sigvat. It leads to his downfall in a way that's supposed to be awe-inspiring but is just confusing. At least he gets his just desserts. Gudrid may or may not get her comeuppance but at least what she gets shuts her up for the last few chapters. The rest of the characters go off on their own and try to forget the whole story ever happened.
I'm going to try very hard to do the same.