Worriedbeef says, "I've heard that a heavier cue is better because it helps keep your cueing straighter and steadier. I suppose that makes logical sense."
The "straightening" effect of a three-ounce difference in cue mass is trivial. It takes very little force to overcome a cue's inertial resistance to sideways motion enough to spoil one's aim. For one thing, the bridge acts as a fulcrum, greatly reducing the amount of force that must be applied at the handle in order to move the cue tip sideways a given distance. Just take a few practice strokes with 18 and 21 oz. cues, and see if you can detect any difference in the effort required to pivot the cue tip away from the cue ball's center.
Billy_Bob says, "with a very light cue, it can be difficult to shoot very fast shots."
I don't see why that would be the case. More of the force that accelerates the cue is wasted in overcoming the heavier cue's greater inertia, leaving less force to be transferred to the cue ball.
The difference in inertia between a lighter and heavier cue is most significant along the cue's axis, because all of the cue's mass is resisting change of its speed in the same direction. So it is noticeably easier to apply a precise amount of force to the cue ball with an 18 oz. cue than a 21 oz. cue, giving one better control of the cue ball's velocity.
The distribution of mass in a cue, as measured by its balance point, affects the cue tip's tendency to move up and down during a stroke. The tip of a butt-heavy cue will tend to rise as the relatively great mass behind the bridge point pulls the butt down. The tip of a forward-weighted cue will tend to fall as the far end of the cue extends further past the bridge point, because more mass gets out there pulling the tip down.
Alstl says, "Somebody who sells cues for a living told me that most of the medium and higher value cues he sells are between 19 and 20 oz."
I suspect that is a function of the materials that go into a fancy cue: dense tropical hardwoods, ivory, semiprecious stones, metals, etc. If you buy such cues, you get accustomed to such weight ranges. Yes, a butt's mass can be reduced by coring and other techniques, but there's a limit to how much mass one can eliminate without turning an ebony butt into an ebony veneer. I suspect that limit is around a 19 oz. total weight.
During four decades of playing, I've become adapted to cues of around 18 oz., with a balance point about two inches ahead of the wrap area. The butts of my cues have very little mass-adding adornment. I like the simple, elegant look of fine woods. Plus, they're cheaper.
Maybe so of them will prove valuable for my grand kids (if i ever have any).
