There are no absolute’s….. but if the limb design is the same, with the fades in the same location, and the unstrung profile matches up at the same angle, both the one piece and TD should perform the same.
Most bowyers that have developed their own unique limb designs start out with the TD version so they can adjust limb pad angles, taper rates and wedge locations, as well as get the brace height established. Once the design has tested as a winner, you can reverse engineer it into a one piece and get the same performance with a lighter mass weight.
With that being said….. the TD bows are much more popular for many reasons. Traveling is a big one, and having an extra set of limbs built is another. I know a lot of guys that have lighter weight limbs for 3D shooting, or just getting back in shape after a long winter. I build a couple different designs that I can mount recurve limbs and hybrid long bow limbs on the same riser…..
.02 cents worth ……. Kirk