Frigatebird
I guess this type of thing happens where there are differing names for similar things and the different logbooks from various administrations don't have the same names for things and don't have the same columns.
There is Command Practice (no ICUS or any other similar thing) in NZ which is similar to ICUS though I couldn't be sure they're the same thing by exact definition. Command Practice is done in the RH seat while flying the line with a line Captain though in many cases there are some limitations on when a Co-pilot can log Command Practice and which Captains may give it. For the Co-Pilot to be in the LH seat he/she must fly with a Training Captain. This normally occurs when doing the line training for a command upgrade, however is still only logged as Command Practice at best, it cannot be logged as P in C.
I still fail to see how they could log P in C and expect anyone to accept that they were P in C.