In answering the question, to be blunt, you shouldn't be 'timing' your progress. It's not a race. It is the ability to play. While it's possible to 'get through' the lessons in short order, how much did you retain? How much can you replicate in your playing now without having to refer to the lessons? If you were to be in a conversation with someone and they were talking about a certain mode, would you be able to not only understand the overall idea but be able to understand how to apply it?

The point being is that, I don't think, learning the basis for playing is something that you 'get through' in as much as you use it for the basis from which you grow and refer back to it regularly.

Folks that've seen me around here enough can ignore this but...I've been playing for 25+yrs off and on, taught a bit in my years and was a shredder in my younger days. I came here to grow some in my playing and still find that the first three chapters of Fund2 worth a review.

These things a building blocks and something that isn't really about how fast or slow you get through them but a matter of how integral these ideas and skills build in to your playing.