I love the way you explained this! I feel the same; this book was the key to making me a tower junkie and putting my feet on the road with the ka-tet.
It wasn't a road to Damascus kind of thing; more like skipping the spiral that starts out the yellow brick road.
Somehow, the way SK describes the struggle to draw Jake and complete the tet is a call drawing the reader into the tet as well.
This is certainly my favorite of the series for that reason; it welcomed me into the quest.