Much of Mo's advice seems to revolve around the idea that bowling is a business and that in order to make money, pro-shop and centers need all those people who just go in for 3 games of league and really can't roll it that good, to have amazing ball reaction.

Thus, my impression that quotes such as pin down "don't work" is because you are not getting the most reaction out of a ball that is going into the hands of a mediocre  bowler on an easy house shot, and you want the ball reaction to be great no matter how it is thrown.

I suspect that this has led to certain bias on his part. The recent video of him talking about urethane, and saying what seems to be ridiculous things - such that the pro's will have like 5 urethane balls in 1 tournament, and they can only use it for like a game or two and then the surface is gone, and they have to have reps do all this work on the balls. Well, it was sort of absurd.

He does sort of have point however. If bowling in a business, and we need all those mediocre bowlers coming back each week and also convince them to buy a new ball each year, then selling them urethane doesn't make any sense.

And sure, if you need to get every possible board of hook from a speed dominant bowler with 175 rev rate on house shot - to make them feel great about their  bowling without them actually bowling better - Yeah, better drill 4 inch deep thumb holes, of widest slug you have to maximize hook and whatever other tricks Mo has.

I'm not criticizing this perspective. Just saying that when his quotes circulate that pin down "don't work," it's probably best to  just ignore it, unless you run a proshop and need to sell a new ball to the below avg league bowler who wants to buy more hook.

Despite having throwbot and videos of pin up and pin down balls being very similar for most bowlers Mo focuses on core numbers.  More has to be more better despite the differences being hundredths of an inch when comparing pin up vs down.

In his seminar on comparing the two he uses a 5" pin down vs a 3.5" pin up….. And the pin up flared more and had a "better"  pin to spin line etc.  When you have to skew numbers to create a difference and make your point valid it's sad.  You muddy the waters and make it harder for people to learn and have a correct understanding of what really matters in ball reaction.