I still find it laughable that we keep changing cue length and measure the balance point from the butt.
I run 59" cues, and a CG 40.125" (40 1/8") which is close to the "19 inch" balance point listed above.
on a 57" cue, a CG measured my way would feel the same, where a 19" CG (Center of Gravity) would feel way off.
It's pretty simple:
If you measure the cg FROM THE TIP and make it the same regardless of overall length, you'd have the same "feel" for different cues.
You set up your whole address from the ball rearward, measure the CG from there.