I like Dr Dave. I believe 99% of what he contributes to the pool world is accurate and of good value delivered with good intent.
Particularly the large amount of instructional videos or information videos on aspects of the game that no other book or instructors would ever cover and would fall into the realm of "pool secrets" you'd have to pay for, aka learn the hard way.
Dr Dave is not perfect as no human is. I applaud his efforts to dig into various areas of the game and equipment to figure things out. Early research and testing is rarely perfect or conclusive. At least he is doing it. Whereas most people do nothing, and spend their lives speculating, wondering or creating theories as to why/how/what happens in pool. Turning the web into a cyber version of the types of bangers you see loitering in pool rooms perpetuating myths about the game.
A month back I started a thread asking if there was any recent development of a cue stroking machine. Particularly to test LD shafts. There aren't any new ones. The ones that exist are owned by biased entities (Predator & Meucci).
Without a machine to do the testing, it is impossible to get solid results.
However, an individual can get a good idea of what deflects more or less by shooting the shot DD did in his video. That same exact shot is what I used to test deflection back in 1999 when I first tried the original 314. Center of table, shoot straight to the diamond, use same amount of side spin, use the same speed (judged by where the CB ends up)....observe where the CB hits the cushion.
This is more than adequate for simple tests. Comparing a Predator 314 to a Meucci, Schon and others it is easy to tell the difference.
The reason I asked about a cue stroking machine is because AMONG LD shafts, particularly the very newest ones...the differences are small. Small enough to possibly be user error, subconscious steering ....or whatever.
Look at the Platinum Billiards data...for example. Relative to one another, the LD shaft section is quite close. I personally can notice the difference in deflection from any 314 to a any Z. That is noticeable. However, from the 314 to 314-2, I cannot. I want to SAY I can, because I know which shaft is which and I know that it is said the gen 2 has less deflection, but I cannot tell in a reliable fashion. It feels a tiny bit less after lots of shooting and testing, but I can't honestly tell myself one way or the other because I know the difference is so small, the variation in my stroke is almost certainly larger....
That said...I can tell LD shafts apart in "groups" ....Z shafts, easy. 314's ...Meucci which isn't a LD but the lowest of the standard shafts. Cues like Joss, Schon and the others have massive deflection.
It gets tough when you mix in OB and others. Some of these are very close. Also, since the Platinum data there's been many new LD shafts and many revisions to existing ones.
You then begin relying on the "cumulative" results of your experience and feel. I believe that can be accurate, but it isn't data. The consensus seems to be right about the various LD shafts.
It would be nice to have hard data and be done with it. But until someone puts up to have a high quality cue stroking machine built - and does so with an intent to remain independent and neutral...all we have is consensus.
Now, there's an indirect way to do this. One can buy a few samples of each shaft - cut sections of the shaft end and weigh them. The shaft with the lowest end mass with have the least deflection. Also, the shaft with the lowest end mass at the furthest point (near the tip) will deflect less than shafts of the same weight but different mass distribution. Yes, there's cons to this - but this would be a lot more accurate than human testing and probably more accurate than primitive cue stroking machines.
That said...Predator has designed and made the lightest end mass shafts. The REVO is lighter on the end than the Cuetec. Cuetec elected to use that short ferrule which extends down into the CF tube.
Other manufacturers have used Predator's concepts to create LD shafts. However, for whatever reason, none have surpassed Predator in LD. I'm thinking a part of it is patent infringement. While some of Predator's patents expired, they have others. Part of it can be the fact that most other manufacturers don't necessarily want to create the lowest deflection shaft possible. Maybe they value a particular "feel" or feedback of a shaft. Or perhaps they don't want to invest in what Predator has to manufacture such thin walled wooden shaft ends that survive that kind of stress. Either they can't do it, or can but it costs too much. Perhaps Predator has an edge in their manufacturing process that makes building these shafts more profitable with less warranty claims. I'm speculating here.
Mezz comes to mind. Their shafts fall into the LD category. Are they all out LD? No. But on the other hand, they have far better balance and feel than any Predator. That's a worthy trade-off for many players.
OB tries harder to be as LD as possible and for any practical purpose - they are essentially as LD. Their designs were obvious attempts to work around Predator's patents.
Look at Cuetec's very own words regarding their Cynergy shaft's mission-statement.
"With such a premium placed on deflection results over the past decade, feel and feedback had been left behind, replaced by percentage points and equations that had little to do with how the shaft felt or how much information it transmitted to the player wielding it."
Cuetec is admitting they are not going for all out LD.
This is what Mezz players have felt literally and figuratively. A few percentage points of LD means nothing...but some improved feedback and feel does. While that can't be quantified scientifically - all I can say is, if you have never played with a traditional maple shaft to at least a B+ or A- level ...then you don't know what you are missing. Feedback and feel does matter.
Thus, Mezz fans always say the same thing - the shafts are LD and that's great, they aren't the lowest possible, but the feel of the shaft is an overwhelmingly larger factor than a minuscule amount of deflection. They are all universally happy to trade all out LD for having good feel and feedback.
Predator players (many, not all) have lamented the loss of feel and feedback. However, like Mezz players, they were happy to make a trade-off. The loss of feedback and feel, to save a LOT of deflection relative to old school shafts from cues like Schon for example.
Predator has always gone all-out for low deflection. These other manufacturers, partially because they can't match Predators LD performance and partially because they want to differentiate themselves - try to go for LD with some feel.