That's a good curve ball, It happened to me where 3 rated pilots were flying 2 single pilot aircraft, we were "double crewing" 2 aircraft 1 B204 and one B205, those 2 aircraft went non-stop for 16 hours a day everyday (short term) we did one entry for the date on one line with our names in each journey log, we were using split duty at the time. Difference here is there was only one pilot at a time in each aircraft with dual controls installed, everybody was flying left seat (Bucketing). Our flight time was recorded in our "Flight Duty" record for the day.
JD