This is one of the most confusing rules that depends on how it is interpreted. I'm an APD at a 121 carrier. When doing this certification under our program it was understood as 1200 initially with PIC + 1/2 SIC. This was incorrect as it had to do with helicopters. It then went to the PIC + 1/2 SIC= 1500. This then was changed to being read as as long as the governing body (FAA...I believe) determines you can use all of your SIC + PIC to meet the 1500 requirement then you don't need the restriction. This is now how we do it under our program...until it changes.