I can only think of one objective difference in performance between heavier and lighter cues: a lighter cue has to be stroked a little faster than a heavier cue to get the same force into the CB, and you may be more comfortable/accurate with a faster or slower stroke - personal preference, but for an objective difference in performance.
What else am I missing?
pj
chgo
One thing you are missing is that there is only a certain range you can compensate for. I could probably build an eight ounce cue. I suspect nobody could play with full sized pool balls or heavier with it. If you managed to generate speed, control would be long gone. I mastered a twelve ounce cue. It took several months and few people played my style of pool. I have never seen anyone else use a 12 ounce cue really well on a pool table. I was able to win weekly tournaments every week until I had to quit beating up on the regulars with one.
As I have written before, grab a sixteen, twenty, and twenty-four ounce carpenter's hammer at a do it yourself store. You can drive a six penny nail with a twenty-four ounce hammer and a thirty penny nail with the sixteen. You won't keep up either effort long!
I think it obvious that most people favor a 19 to 19.5 ounce cue. Seems to be a strong indication that comfortable stroke speeds match well with a 19 to 19.5 cue. Not the only thing that can be made to work, my cue is sixteen ounces, but few like my cue!
I have played with 12 to 26 ounce cues and with a 32 ounce cue. If I was going to hit straight in shots all day for a week I would probably choose an eighteen to nineteen.five ounce cue. Too much work with my sixteen and too much effort catching the cue with a twenty plus ounce cue.
Incidentally, hammering nails for a week or more, eight or ten penny I like a twenty, sixteen penny or larger I like the twenty-four. Twelve penny depends on the job. Back when I was young and dumb and fulla beans I swung a sixteen pound sledge with the best mechanical efficiency. Didn't stop me from using a twelve when I could, less work even if less work was done at the end of the day too. I was getting paid by the hour.
I suspect there is an ideal weight and velocity for most tasks. The further we get from that "Ideal" the harder it is to pocket balls and get shape. The further our body size and build is from the norm the more likely we are to want to go outside the normal cue weight range.
Hu