JD
Correct me if my recollection of the time frame is a little fuzzy but I believe that the L model had plenty of excess performance allowing G-12 to lift the load and climb straight up. The only limits that were approached were hook and airframe structure. I believe that at the time some consideration was given to providing a bridge from the MGB to the hook eliminating any airframe structural issues.
Also as a side note, the Two Malaysian VIP S-70s cost a total of $30M. That got them two heavily modified machines that incorporated Honeywell EFIS, Seahawk AFCS and a complete spares support package. The basic FMS UH-60L was about $10.5 at that time.(circa 1997)
Cheers
Jack