"Front end mass" is an idea that (counterintuitively) encompasses several factors. Dr. Dave writes about stiffness specifically:
http://billiards.colostate.edu/threads/squirt.html#endmass
So, assuming that the G-Core's carbon fiber cylinders increase stiffness without meaningfully decreasing mass (because they are so thin), I would expect a G-Core shaft to impart more squirt than a regular maple shaft.
According to Dr. Dave's testing, McDermott's Intimidator shafts are pretty low deflection but I think that must come down to how skinny they are. Any extra stiffness from the carbon fiber cylinders must be negated by simply having less wood at the front (and maybe a smaller/lighter ferrule?).
So I guess I'm still confused about why McDermott's mid-tier shaft seems to be designed on purpose, according to their advertising, to give a stiffer (and thus more squirt-imparting) hit. Is it because they think the hit feels better, or because a more rigid shaft seems intuitively better to potential customers who don't know about Dr. Dave's analysis on squirt, or is it possible that they designed these shafts without knowing what causes (or reduces) squirt?
This is a great series of questions. I'll try to clear it up for you.
Stiffness has very little to do with the amount of squirt. It has a lot to do with how the shaft feels, how you perceive the "hit", and probably whether you like playing with it.
It is primarily the mass of the end of the shaft that affects squirt. Many companies *replace* the wood with either a hollow space, or a material that is lighter than the wood itself. Remember that the structural strength of carbon fiber is quite a bit greater than maple wood. Thus a thinner and lighter piece of carbon fiber can be be used to achieve the same strength as a larger and heavier piece of maple.
It would appear that the G Core idea is to replace some of the wood with carbon fiber. As far as I know, this is exactly the design philosophy in Cuetec's R360 line of shafts. Cuetec, I would argue, implemented this concept far better if indeed the objective was to reduce squirt. The R360 has considerably less squirt than the G-Core.
If the goal of the G-Core design was strictly to reduce cueball squirt, then I would say this lends a lot of weight to the idea that they designed these shafts without knowing what causes squirt.
I have played with the i3 shaft, and I can tell you it has quite a bit less squirt than the G-Core. Not nearly in the league of something like the Predator Z2 shaft, but much less than the G-Core. The G-Core might have a hair less squirt than a regular maple shaft, but really the range of possible squirt for all the various millions of solid maple shafts is all over the map. I've hit with an old Southwest with an original micarta ferrule, about 12.5mm, that required almost no adjustment from the 314-2 Predator I shot with. However this is HIGHLY unusual.
If you can get yourself to the Super Billiards Expo, you can try out all these different shafts within a short time of each other and get your own comparison. I would recommend trying to shoot balls in with loads of english and see how you do. There are plenty of reference shots you can set up to test out the squirt of a given shaft.
The term high deflection sounds odd. I think, though, that the short answer to your question is that the G-Core is not a low deflection (squirt) shaft. It is pretty much in the ball park of most standard maple shafts, maybe a hair less.
Hope this helps,
KMRUNOUT
