The winner!!
Follow the science. A harder tip will not absorb as much Kinetic Energy(KE) as a softer tip allowing more energy to be transferred to the CB.
OK so you pick up a foot pound of kinetic energy, Yaayyy, so what!
Going from a 21 oz cue to a 25 oz cue at 26 mph will add around 9 foot pounds of KE. Whooopeee!
KE energy is Mass x Speed. Let's say your arm weighs 10 pounds, and for a lot of players they use the same stroke for their break as they do their normal shots. So they are using their forearm only, going as fast as they can. They may look like they are using their shoulder and upper arm but usually all that comes into play after the CB has already left the gate, on their follow through!
Look at SVB's break, as critiqued by Dr Dave, on youtube. SVB engages his shoulder/upper arm before contact with CB. Most players are swinging a mass of 101 ounces(weight of 21 oz cue plus 5 lb lower arm) at 26 mph. for around a 193 foot pounds of energy. They then go to a 25 ounce and add approx 9 foot pounds of energy. Add the upper arm and double the mass at 26 mph with a 21 oz cue and you've gone from 193 foot pounds to 346 foot pounds of energy. Easy to say but difficult to achieve. That's why SVB looks like he's hardly swinging at all, no need!
Would you rather be hit by a semi at 26 mph or a VW Beetle at same speed? Mass matters!! Get the upper arm/shoulder involved! Pro boxers don't swing from their arms, shoulders, or hips. They swing from their feet which involves the whole body