Todd,

To put it simply..they don't have as much "snap"..

If you look at the very fastest bows on the market you will see that they all have much more limb travel due to longer length limbs (comparitively) and the angle they come off the riser...(causing them to have to bend farther still..more stress)

In the case of short/parallel limb designs: they "load up" and can't get that arrow moving as efficiently since thy don't have the momentum/travel...It's the long lever vs. short lever syndrome....longer limbs(or levers) have more leverage...when there is less limb to do the work, and less stress applied, the system does not work as efficently..as the arrows get heavier..it has to work harder to move that mass

In the case of the Patriot..the levers (limbs) are bit longer, the cam is more agressive, and it seems that they have figured out through trial and error a better level of Pre-load or "stress", while retaining the major benefits of the technology in general.

And yes I have done other reviews here, though not quite this exhaustive...A search for "Bow Report" in the technical forum should turn some up.

JeffB