I realize that every grit is a both a traction and shape grit, because when you change the surface, you change both of those things, but traction is the primary benefit/reason you use 2000 or under, shape is the primary benefit/reason of going higher. 

I will TRY to get video to illustrate my point, it's just a challenge and a lot more work involved putting all that together.  Also trying to keep it short and sweet, most people don't want to sit through a minimum 15 minute video and that's what most of my ideas lend themselves towards.  I realize sometimes there aren't any shortcuts, but finding the time becomes difficult at some point.  I've been ready to make another Beer Frame video for two months now, just haven't gotten schedules to work out yet. 

On a side note, 3000 or 4000 grit can do similar things that 2000 grit does, for normal/average (rev/speed matched), for strong, grabbier coverstock/Strong cores.

In my view, anything from 1000, 2000, 3000, or 4000 can be benchmarks or ball reaction shaping grits, depending on both the strength of the bowler's delivery and the strength of the coverstock.  It always involves all the factors and their interrelationships. The factors are too tightly bound up with one another to separate them.

2000 grit can be your dividing line depending on the strength of your delivery and the ball you are using, or it can be 1000 grit or it an be 4000 grit. You cannot and should not put an arbitrary dividing line at 2000 grit. It is too restrictive.

Realize that 2000 for one isn't the same as 2000 for another.  I like the idea of explaining the effects of grit on the reaction/shape, but to be aimed at the "masses" the use of more than one style would be preferred. 

I know this throws a wrench in the idea perhaps, but for most people, they believe what they see and not the theory.  You could have the best explanation and demonstration with yourself, but until the typical senior, woman, low/high rev or low/speed bowler sees someone like him/her demonstrate the theory, they will not completely understand.

At least this doesn't necessarily cost additional equipment to show different reactions by different people.  Each bowler could bring their benchmark ball to show the effects.

But any information is still better than no information and your idea Luke is a great one.  The more I think about it, the more of a DB I sound like considering the level of information you already provide.  You do provide a valued product and I personally watch all your videos.