World Without End - Ken Follett

I finally finished this massive book of well over 1100 pages. Ha, it's only taken me a year. It's a huge, sweeping tale of medieval England before, during and after the Black Plague of the late 1340s.
The central theme is the struggle for progressive thinkers to have their new ideas and methods heard and accepted in the face of the intransigent conservatism of the ruling class and, in particular, the Church.
The two central characters are Merthin, the architect and builder, and Caris, the merchant's daughter turned nun. Merthin leaves Kingsbridge, where the story is set, for Italy when his new building methods are ridiculed and sabotaged by the traditionalists in the town guild. He returns, at the height of the Plague, and is determined to construct the tallest cathedral tower in England. At every turn he is thwarted by the guild and the cathedral's prior. Caris becomes a nun to escape charges of witchcraft which arose from her forward thinking approach to life. She leads the town's defences against the ravages of the Plague and is again harrassed and stymied for her medical practices which run counter to those practised (the same way for centuries) by the monks.
The book follows the fortunes of Merthin and Caris from childhood to later middle-age. It's also their love story.
The central themes are important ones but there is a tendency to repeat the same basic scenarios over and over again. New idea meets conservative guild/noble/church -> power struggle -> new idea gains some ground -> conservatives fight back -> new idea thwarted -> conservatives shown up as ineffective or incompetent or venal or evil (or all of the above in a number of cases) -> new idea is given a chance to prove itself -> gradual acceptance of new idea to the consternation and bad grace of the guild/ruling class/church.
The role of the Black Death in changing the basic nature of the Feudal system is also given a lot of coverage. But again, there was a lot of repetition of the same scenarios.
This could have been a great book if it had been two-thirds the length.