Ad now for something completely different-Skid and Margin of Error

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duckie

GregH
Silver Member
Shooting Arts had this comment about my statement that the margin of error of a shot can not be increase with any form of spin or aiming method:

"with respect, your first paragraph is wrong. When in danger of skid for example, aim to make the ball in the nearest edge of the pocket, you just increased your margin of error. We can often make pockets play bigger for the shot we are taking"

I thought about this a bit, slept on it, did some research, which I found this
http://billiardsdigestvault.com/wp-content/uploads/JEWETT_0409.pdf.

Well, I stand my by statement that the margin of error of a shot can not be increased with any spin or aiming method.

Referring to the comment,

1st. Can you for 100% tell when a shot will skid? Can you tell me in the shots pic below which shot will skid and which one will not. You been playing for three hours on that table and with those balls, not not once has a skid occurred. Why would you believe one of these shots will skid and one will not?

If you can, please tell what indications there are that tell you one will skid.

2nd. What do you consider "the nearest edge of the pocket"? Pocket side and which part of the pocket side? The edge of the slate in the pocket? What is the edge of the pocket?

3rd. Even you if you do adjust for skid, how do you know your are hitting outside of the margin of error for that shot, and not just not rationalizing that you are? Referring to the drawing also posted, how do you know you are hitting outside that area when making your adjustments?

Or are you just rationalizing to make it so?

The 6 ball shot has a greater impact zone ( my term for margin of error) than the 9 ball shot. Also, the angle OB/CB angle plays a role in how much of the impact zone you can use.

Distance from the pocket affects the amount of adjust needed. The farther from the pocket the OB is, the less adjustment is needed. In the 6 balls shot, you have a wide range of adjustments you can make and still have the ball go in the pocket. The 2 ball has less than the 6 ball because it is farther from the pocket. The 9 ball has the smallest because of the CB distance and angle to the 9 ball.

You can not just say I am wrong without better proof than what was offered as proof of me being wrong.
 
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I think you should be be more concerned with skid marks in your whitey tighties than pool ball skid.
 
I don't know why I'm bothering but here it is...
There are lots of examples where spin and aiming techniques will help make a shot. For very thin cuts with the object ball frozen to the rail, aiming to hit rail first slightly with inside spin is much easier to make than shooting with center ball, and it makes it possible to make 90 degree (or even greater) cut shots.
Another example is "stiffening up" bank shots with speed and spin to make the pocket bigger like John Brumback shows in his banks DVD.

About skids, once you get to playing at a high level, one skid can cost a player an entire match, so the possibility needs to be considered. For situations where there is a good chance for a skid to occur (i.e. dirty equipment, or getting shape requires a soft, rolling shot, etc.) good players will make sure to shoot with speed/spin or as Shooting Arts said, with aim to prevent it.
 
I agree with what victorl said.

Plus at times there are shots when a ball is blocking & the shot cannot be made with a center hit but can be made with english & some spin induced throw.
 
Been thinking about this more. As such, I have a new term to use called the Roll Zone. In my drawing, the Roll Zone is the area between the two OB direction of travel lines going into the pocket. Using this concept, there can only be a certain size roll zone for any shot.

The impact zone(rather the margin of error, but I use impact zone) on the CB is another matter. Another matter in that it might be possible to hit outside the impact zone( margin of error) on the CB as shown in the drawing, but still keep the OB contact patch with the roll zone for that shot.

The only problem is proving this. So, in this regards, I have rationalized to myself that the Roll Zone can not be made larger by any means of spin or aiming method, but might be possible to hit outside the Impact Zone(margin of error) as shown in the drawing.

So, I am right and wrong at the same time. At least, that's how I rationalized it.

But the answer to the one question about how do you know if you are or are not hitting outside the impact zone is a mystery. But the size of the roll zone is set by the pocket opening size, ball size, distance to and angle into the pocket.
 
Sounds to me like we've got a semantic difference about what constitutes "margin of error." I think of margin of error in a classic geometry-physics sense. In this sense margin of error is a constant; by definition it cannot change.

The other arguments I see in this thread are about changing the percentage-odds that you'll make the shot. Those might be true, but they only change the percentage-odds, not the margin of error. For example, I put a little outside english on most cut shots to counteract cut-induced-throw. It increases my percentage-odds that I'll make the shot because I find it easier to aim that way. But it doesn't change the margin of error I have of where the CB can contact the OB and send it to the target.

I agree with Duckie that there are only three elements that determine margin of error: 1) size of the target (either the pocket or rail area for a bank/kick), 2) cut angle and 3) OB distance to the target (CB to OB distance is irrelevant -- yes, CB-OB distance changes my percentage-odds but not the margin of error). (Also, size-of-ball would be a factor if we were playing with different size balls, but let's assume standard size so it's not a factor).
 
You forgot shot speed... shooting at pocket speed will increase your margin for error and make the pocket play slightly bigger.
 
"chalking your cue," to increase margin of error.

victorl said:
You forgot shot speed... shooting at pocket speed will increase your margin for error and make the pocket play slightly bigger.
Click to expand...

Not to mention "chalking the tip," to increase margin of error. :wink:
 
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