Not sure what YMMV means; not "you made my day" I'm guessing; perhaps some version of results may vary? If the latter, that's really the deal.
YMMV = 'your mileage may vary'.
This brings up the first clarification: not sure why @armoured refers to "minimal travel," but to be clear, your best chance of keeping PR status will be to STAY with NO travel outside Canada until you are in compliance with the RO.
"Minimal travel" is the smallest amount possible, a range which includes - and I would say 'dominated by' (in logic/results) - zero.
Which is to say, I agree: a PR who has been out of compliance, does not have a valid PR card and/or (especially) has undergone an interview at a port of entry that raised the issue of non-compliance / been warned / even been sent to secondary related to this really should NOT travel at all.
But if absolutely necessary, a small amount of travel - shortest possible trips, lowest possible frequency - for needful reasons (emergency, unavoidable work, etc) will be LESS risky, the moreso if that travel happens when closer to being in compliance again.
I'd put that as minimal. No travel at all until in compliance again is better. Small amounts less bad than larger amounts.