Thanks T, so the only scenario in the US for gliders where two pilots
can log PIC time for the same flying time is when a rated and current
instructor does instruction (e.g. commercial) or a check ride (e.g
BFR) with an already rated glider pilot?

I'd be interested to hear e.g. from the UK, AU & NZ how the P1/P2
relationship is handled in a glider with regards to logging PIC time.

Thanks,

Markus