There are several licensing definitions that are confusing (and getting that table above right, believe me, would convince anybody of that fact
)
However, I find it difficult to believe the definition of flight time in this context is hardto understand. The issue is obviously to do with personal experience to retain currency, which must obviously be flight time undertaking a role that is both legal (as P2 in a SEP isn't) and credibly provides that experience.
How a reasonable person could ever convince themselves that acting as a piece of talking airfreight is loggable experience for licensing purposes is beyond me.
To suggest that the regulatory authorities should be pinning down the definition of "flight time" in this context to such an extent is simply farcical.
And if they tried they'd likely screw it up, anyway.