You can log PICUS in a SEP-SPA aircraft but only when you have passed a license/class flight test with an approved examiner.
Same here mate I now have 3 different ATPL's thankfully two of them have decided to use JAR as there base line which is my original first ATPL. But all have differences which can bite your bum.
Unless you have operated in that type of company that does dual crew in SPA types the whole subject is open to wide interpretation. Unfortunately some pilots believe some of the crap spouted on here and end up getting log books bounced back when the apply for stuff.