100/145 = 68.966%Normally, playing Banjo Kazooie and it's sequel, I didn't have to go far out of my way to progress the game. Find the jiggies, get stuff along the way, and I'm good. I don't recall having to backtrack that much at all. From what I read in multiple reviews, to progress the game, you need 100 out of 145 pages to reach the end. That's quite a bit.
In Banjo-Kazooie:
Total Notes: 900
Total Jiggies: 100
Notes required to reach Grunty: 810
Jiggies required to reach Grunty: 94
810/900 = 90%
94/100 = 94%