out of curiosity, are the time for HC + Energize timed or simply calculated empirically??

Since stacking percent bonus/reductions are weird, was there any experiments that can validate the time calculated ?

The time can be either Time*0.85 (HC)*0.35 ( Energize).....which stacks by multiplication
or Time*0.20 , which is stacked by addition of the bonus

and both will yield different results (13.85s vs 9s for Jugg)