The discussion is that OP is asking questions and I'm answering them.
The only other advantage to the laminated shafts I can see is that you can easily unwarp a warped shaft.
Extra spin, I'm not so sure about. The more flexible the shaft the more action.
As for all that radial consistency I don't buy it.
It is as consistent as the weight of those things which can be different by as much as 0.6-0.8oz.
Since no manufacturing process is perfect there is variance.
Radial Consistency is THE advantage..... A standard shaft or LD shaft can perform equally well as long as you identify the pivot length.
LD shafts usually have a pivot point further back than you can find on a standard shaft to the point that many people who try and switch fail miserably because their brain is used to more severe cueing angles of a forward pivot point and refuses to accept that the new angles for the LD rear pivot are so much less as to almost appear that you can parallel aim....
Radial consistency comes in because the grain structure in standard shafts can have a direct impact on the amount of squirt that the cue creates depending on the radial orientation. Notice that I said can... A standards shaft can be close to consistent but in most cases it will be hit or miss because even the better cue makers don't test for consistency but go on tightness of grain and appearance...
Back when predator first hit the market I visited one of their booths at a tradeshow... I was walking by and they had this funky apparatus hanging out front that was basically a couple of wires and a protractor. You can do the test they did at home if you wish by simply hanging the end of the cue off the end of a table and using a yardstick or other means of measurement to quantify the results...
Hang the shaft horizontally so you can mark the base position on your measuring device, I.E zero on a protractor......
Now you will need to come up with several weights that you will hang from the end of the cue... I think they were only using 1pound 3pounds and 5 pounds.... The weight differences are to simulate hitting the ball at slow medium and hard... I am sure there are actual weight numbers that could be attributed to different speeds but I am not an engineer nor do I play one on tv so 1,3 5 it is... even tho that might only simulate super soft, soft and medium soft.........
Start by hanging the lightest weight from the end of the shaft by a looped string over the shaft.... Note how far from the baseline the shaft bends..... Now rotate the shaft and you will likely watch the tip of the shaft move up and down on your measuring device....
If i recall correctly I was using a Russ Esperitu at the time and as my shaft was rolled the protractor readings went from 3degrees to almost 10 degrees. In hindsight I know this was because this standard shaft had a definite spine to it... Old school players used to actually mark the spine and try and keep it facing up or down when holding the cue....
They repeated the test using the predator shaft and I watched as the reading stayed the same as they rotated the shaft... I want to say it was 7 all the way around.... It's been 16 years so the actual number has been lost to Jaeger or Crown......
The 2nd part of the test where you use differing weights is more or less a blur to specifics but I do recall there was more bend to my shaft as the weight increased than there was to the engineered shaft....
The other way to tell if you have a radially consistent shaft is to do the pivot test from drdaves website at the end of this video and rotate your shaft to see if the pivot length changes..... This can be more subjective than the first test since 10% change would likely be less than an inch difference but that difference can be the difference in a make of a miss.....
http://www.youtube.com/watch?v=5T3ai0SM1aw&feature=player_embedded