Bob Jewett said:
If you try to use perfect throw cancellation by using outside english, and you get the english slightly wrong, you will introduce a large error in the cut angle.
Yes, I understand this and it makes sense.
However, I'm talking about using english that is
more than what is needed for perfect throw cancellation. For these cases, the landing point of the CB on the OB would be thicker than the perfect throw cancellation case, since the CB is actually throwing the OB at a greater angle toward the pocket.
So here is my first order argument.
You have a certain cut shot, say a 45-degree cut shot to the pocket. You shoot the CB at the OB at a slightly
thicker angle (thicker compared to the ideal, zero friction case), say at 42-degrees, but you spin the CB with excess outside english such that the CB throws the OB at a greater angle, sending the OB to the dead center of the pocket.
It should be apparent that you're already increasing your margin of error to a degree just by the fact that you are shooting at a thicker angle than the zero-friction case, since the margin of error increases the less cut angle you have.
Next, you have the exact same shot and you shoot the CB with the same speed and the same amount of spin, but this time you hit the OB slightly fuller than the first case, say at 40-degrees instead of the previous 42 degrees. For the zero-friction case, this two degree difference would translate to a two degree delta in the CB departure angle. But for the real world case with excess outside spin, the CB departure angle would only be
less than two degrees.
Why? Because you're hitting the OB more full, and CB/OB throw would have more of an impact than the previous case. Therefore, friction would only make the change in departure angle be less than the two degrees for the zero-friction case.
One can even argue that because you're hitting the OB more full, the surface speed of the CB at the CB/OB contact point is greater than the initial case, providing even more torque on the OB throwing it even further, compensating even more for the initial hit error.
So at least for the case where you err on a fuller hit, you have three ways that spinning the ball in increases your margin of error...
1) Spinning the ball naturally makes you hit the ball thicker to begin with, and a thicker hit intrinsically increases your margin of error since your error goes up as the cut angle goes down.
2) The fuller hit transfers more of the CB oustide spin throw to the OB.
3) The fuller hit means that the CB surface speeds at the contact point is greater, providing more throwing force to the OB.
Before anyone jumps on me for point #3, I understand that it can be argued that the coefficient of friction can go down with higher surface speeds (which is why you have less apparent throw at harder no-english shots than softer shots). So there is probably not as much increase in error margin the faster you spin the OB.
