I can't see any reason why two people who are legally allowed to fly an aircraft shouldn't share P1 time for a single leg between them as long as this is agreed in advance - I don't know anywhere which says it's allowed, but I also don't know anywhere which says it isn't allowed.
However, as others have said, if you're not checked out on the aircraft, and club rules require a checkout, you are not insured, therefore you can not log P1 in this case.
Two points from your last post:
the reason I haven't bothered getting checked out on the 172, is that it is more expensive than the 152 for self-fly hire, and I AM ON A VERY TIGHT BUDGET
Weight+balance permitting, you can get 4 people in a C172, which means you can cost-share with 3 other non-pilots, thus reducing your costs considerably!!!
I need to log 10hrs this month or else my PPL is dead in the water
You do not need to complete the 12 hours to revalidate your license - you can also do the revalidation by test. Just do as much training as required - which might be as little as 1/2 hour or as much as 5-6 hours - and then a test which lasts a couple of hours. Less hours, and therefore less cost, than revalidation by experience. Your local flying school should be able to go through the details with you, and arrange whatever instruction is necessary as well as the test with an examiner.
FFF
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