The problems really happened after that: too many side plots and characters weighing down the story, a bizarre and deluded notion that Jordan had to "get" characters to certain places and we had to see every step of it (and know every horse's name along the way), bad plot changes to avoid fans having "guessed" things, and a pace that became glacial as a result.
When those flaws came out, other flaws in Jordan's writing ability that I had overlooked became more noticeable - if you have a pace that slow your inability to make lifelike characters becomes a lot more obvious. The slapdash nature of your "world" starts to show through a lot more clearly. The stupid inconsistencies become glaring errors. It's like the mistakes in action movies - when they flash on the screen for a second, most people don't notice them, but if the whole movie were slowed down people would laugh at it and not take it seriously. That is Jordan in a nutshell.
The problem is that because we're talking about a failure in Books 7-14 of a series, I just don't think it could have been redeemed (which is also why I won't blame Sanderson the way many around here like to). The fault was Jordan's. He created the fatal error, and if Sanderson's writing made it a bit more obvious at the end, it's still the fault of its creator, not the person who picked it up to try to finish it.
The encyclopedia was just a reinforcement of what we already knew. It was a grasping money-making pile of shit that was just churned out to try to cash in on a fading brand while there was still time. It showed the same disregard for fans that the later books did - "They're so eager they'll eat up whatever shit I shovel at them". It also finally proved just how much Jordan let the story get away from him.
ἡ δὲ κἀκ τριῶν τρυπημάτων ἐργαζομένη ἐνεκάλει τῇ φύσει, δυσφορουμένη, ὅτι δὴ μὴ καὶ τοὺς τιτθοὺς αὐτῇ εὐρύτερον ἢ νῦν εἰσι τρυπώη, ὅπως καὶ ἄλλην ἐνταῦθα μίξιν ἐπιτεχνᾶσθαι δυνατὴ εἴη. – Procopius
Ummaka qinnassa nīk!
*MySmiley*