Is there that much of a difference in ball reaction between the two?

Its not a huge difference but it is noticeable; especially with balls with medium to high differentials.

Typically a pin down compared to a pin up will start up a couple feet sooner but be smoother overall on the backend because flare is reduced. A pin up ball will tend to go a little longer and have more angle on the backend.

Here is a video I cut and edited for a friend.  Get pen and paper and take notes of 5 shots using a pin up and a pin down ball and see if you can guess what the reaction is....or if you notice a difference.

Not much difference at all, except the first ball looks to be a bit lazier off the spot.  so which is which?  My guess is that 2,3 and possibly 5 are pin-up.

Ha ha, I was too intent on watching the ball reaction, and never even noticed the grayish pin on the ball.  Maybe if the pin was white, lol.  I'm surprised there isn't a noticeable difference because of the Val angle.

One thing to notice though in the video is that their spraying the ball back and forth between the 3rd & 4th arrows, so their playing different lines, so the comparison is flawed somewhat.

Also with that camera angle all you really see is the right and left movement. You cant really see any front to back changes in length.

The whole pin up pin down discussion is a mess.

First we had pinup pindown

Then dual angle layouts come along and Mo and others say pinup pindown is just changing the val angle and depending on the pap etc. using pinup pindown terminology is meaningless, outdated thinking.

Then its decided by Mo and others that dual angle doesnt really apply to symmetrical balls.

So what do we have in the radical drill sheets, that Mo /Radical will point you too when talking about laying out symm. Balls.  Pin up and pin down layouts.

Now they radical dont use those terms, they have pin over, pin below, pin beside.

But you can see how this can confuse a issue, when the guys that tell you something is meaningless, turn around and use the same meaningless terms to describe their layouts.

There is no flaw. It is a human bowling, not a machine. We are humans bowling that will spray the lanes. This is the big difference you will see as a bowler if you went out and did the same thing.

(Note I should have said playing not "spraying" the ball back and forth between the 3rd & 4th arrows. Spraying is more leaking out and pulling shots, where as he was moving and playing different lines)

It's a flaw depending on what is actually trying to be proved or shown.

If you have two different things (layouts on a ball in this case) and use them in two different ways, just because they both get the same result doesn't prove there is no difference in them.

That would be like taking a plastic ball, standing all the way right,throw straight at the pocket, get a strike. Then take a resin ball stand all the way left, swing the lane, get a strike and say there's no difference between plastic and resin because they both got a strike.

By not using them the same way, it doesn't really show if there is a difference or not.

Now if you want to say do to bowler inconsistency, layouts (pinup, pindown etc.) might not be that important. That might be different.

Dual Angle layouts changed nothing about actual layouts. Layouts are the same. It gives you coordinates to easily recreate the exact same layout from ball to ball and for different bowlers based of their pap.

In the end you can be as technical or un-technical as you want with bowling. If the bowler has a ball pin up or pin down and you go through and find the dual angle numbers it doesnt change the layout or ball reaction. People think that the DA is an exact on ball reaction and eventually learn it is not. It gives you some better understanding of the possibilities for the layouts affects on the ball reaction but not any absolutes by any means.

Nothing has changed in bowling or layouts as much as you think from years ago. Only concepts and names are added along with better understandings of things that are relevant and things that are not.

I agree, Basically that's true.

IMO a lot the problem with the Pin Up / Pin Down terminology, is people just see the "Pin" and don't factor in (or know there are) other components like PAP, MB etc.

They just think you put the pin here and it does this. And while the pin "there" might do "that" for one person, it might not do "that" for you.

As you mentioned in your post. Industry people go one way saying one thing and then back the other way about the same subject.

and that's a problem.

You get kind of this " If one company does it it's outdated thinking, if my company does it, it means something or we improved it actually made it work."