Dr. Dave Two Rail Kicks

[7stud]

Dr. Dave discusses the Mid Point Parallel Shift System in this video:

Dr. Dave seems to state that as the angle of the CB gets flatter into the first rail, then the steeper angle into the second rail makes the spin take more and therefore the CB goes long. Then he inexplicably (to me!) says that to correct for that, you need to hit the CB with *more* spin. Huh? Normally, kick systems state that if you add more spin, the CB will come up shorter, which my mental model understands this way: with more spin, the angle coming off the first rail will be flatter and consequently the CB will hit the second rail at a steeper angle. I guess I don't understand Dr. Dave's reasoning there.

A little bit later in the video, Dr. Dave says that as the CB angle into the rail gets even flatter the CB will once again go long off the second rail, but this time he says the correction needed is to hit the CB with *no spin*. Is that because at really flat CB angles into the rail, the spin has no effect off the first rail, so hitting the CB with no spin will cause the rebound to be steeper off the second rail?

Thinking about it a little more, I believe hitting the CB with running English has two effects:

1. Flatter angle off the first rail.
2. Flatter angle off the second rail.

However, those two things have opposite effects: A flatter angle off the first rail makes the CB hit the second rail at a steeper angle and go short, while a flatter angle off the second rail makes the CB go long.

I'm a little confused at this point.

 

[BRussell]

Thinking about it a little more, I believe hitting the CB with running English has two effects:

1. Flatter angle off the first rail.
2. Flatter angle off the second rail.

However, those two things have opposite effects: A flatter angle of the first rail makes the CB hit the second rail at a steeper angle and go short, while a flatter angle off the second rail makes the CB go long.

I'm a little confused at this point.

Right, but English has a bigger effect when the angle in to the cushion is steeper, right? For example, if you shoot straight into the rail, i.e., at a 90-degree angle from the rail, the English can make the ball come off at, say, a 45-degree angle, which is a 45-degree change in the natural angle out. But when you're at a shallow angle, say 20 degree from the rail, at best you can make it come off just a few degrees more shallow.

In addition, when you're shallow coming into the first rail, that means you're going to be steeper into the second. So when you use more English in that situation, you're going to have more effect on how it comes off the second rail than how it comes off the first (because English has a bigger effect on steeper angles). And the converse is true as well: When you're steep on the first rail, you'll naturally be shallower on the second, and so more English will have more effect on how it comes off the first rail and little effect on how it comes off the second.

I don't really understand how that applies for this two-rail kick system. All I know is that generally this system goes wide for me, and running English brings it in tighter. I know that doesn't really square with what I said above, but that's how it seems to work for me at the table. Maybe the typical angle on this kick is usually just steep enough that the running English usually tightens it up.

 

[dr_dave]

Dr. Dave discusses the Mid Point Parallel Shift System in this video:

Dr. Dave seems to state that as the angle of the CB gets flatter into the first rail, the steeper angle into the second makes the spin take more and therefore the CB goes long. Then he inexplicably (to me!) says that to correct for that, you need to hit the CB with *more* spin. Huh? Normally, kick systems state that if you add more spin, the CB will come up shorter, which my mental model understands this way: with more spin, the angle coming off the first rail will be flatter and consequently the CB will hit the second rail at a steeper angle. I guess I don't understand Dr. Dave's reasoning there.

Sorry for the confusion. I should have presented that a little differently.

When the angle into the 2nd cushion is very steep, you need to use less spin (or change the aim toward the pocket), as described and demonstrated here:

But when the angle into the 1st cushion isn't too shallow, using lots of spin makes the CB go shorter, as demonstrated here:

Again, sorry for the confusion. Maybe if you watch the entire video again with this in mind, it might make more sense. Here's a concise summary of the important things to know: