The ATP requirements allow "SIC as PIC" to be used for Total PIC, PIC XC, and PIC Night. We have a requirement that the SIC must have a signoff in their logbooks with the PIC's signature to show they operated as "SIC as PIC". Logging as PIC can't be done, however keeping track as "SIC as PIC" in it's own column would be simple enough, or just mark those pages you acted as PIC. We don't have an MOU with our CMO (Certificate Management Office), this is straight up in the regs, however for the purpose of proving you acted as PIC, a record needs to be shown to show you meet the requirements.

As far as the ICAO restrictions: This changed back in 2009, but nobody really caught on til this last year. It changes to the requirements of "Annex 1 (Personnel Licensing) of Article 39 of ICAO" (Good luck finding it, you gotta pay to get it). Our CMO looked into it and found that for Airplane Multi-engine land, it is 1500 hours of total PIC time, of which all SIC may be counted towards that provided that aircraft has an SIC required for operation. For an aircraft that doesnt' require an SIC, but company requirements require there to be an SIC, I believe you can use 50% of the SIC time toward this. This ICAO restriction only limits flying PIC in the states, so after a year on-line, any Company DE or FAA inspector could remove this restriction with the proof of time.