The Motion Kenpo (Red Book) curriculum was setup by Mr. Parker a long time ago. I think that if he were still alive he would have drastically simplified the earlier curriculum to deal with basics more AND keep the students engaged.
The white belt techniques deal with straight punches, roundhouses, grabs, kicks, and a bear hug. The mechanics to deal with each of these is VASTLY different so the student is forced to learn a large range of completely new physical movements. Their brains and bodies are already overwhelmed with this new information, yet we toss on more. Moving up in belts, it only gets worse. This complexity even in white belt makes it difficult for the instructor to concentrate on what matters, the basics. If he/she tries to correct a basic, then something else gets thrown out the window because there is simply too much to learn.
Who cares about having one response to a bear hug if you haven't dealt with all the most common attacks yet? (Left and right straight punchs, left and right roundhouse). White Belt doesn't come close to dealing with these most common attacks. A student should leave white belt having learned some basic movement to deal with these attacks, not be dealing with the rare bear hug from the rear (In comparison to how common a punch is). Repetition on these attacks is also key. I suspect, if we do the math, the typical student doesn't see all of these common attacks until a few belts in. Even then, how many times have they been attacked this way in a controlled environment? Not many, because time is spent on bare hugs, grabs, etc...
Simplifying what the student learns early on goes a long way to freeing up the instructor to concentrate on the basics. If the student only has to worry about the four major attacks (as stated above) then their brain is free to make adjustments and learn in layers. They get the gross movement then we, as instructors, refine it over time. Each technique is different, but incorporates these same foundational basics. In SL4 we don't teach the white belt (What you would call white belt) techniques until brown belt. Everything up to brown deals with the most common attacks in a very simple form. Here is an example of what you must know to move from yellow to orange.
Simple. Deals with two punches. Allows us to focus on the students stances, blocks, and how they integrate. These pattern continues up to brown and beyond. We layer in new movements at each level and deal with different ranges at each level. Each belt level has a theme as well. Obtaining distance through footwork, obtaining distance through contact, kicks as a response, double punchs, elbows, low high, high low, etc... very simple.