A little harsh I feel... Given the difficulty I've had recently with airlines autocancelling segments I'd be a little concerned if what I was seeing in the underlying airlines' PNRs didn't match what I thought I had booked. And it is perfectly legitimate to be looking at them for seat reservations, inputting Advanced Passenger Info and so on.

But the explanations stack with my experience - the "for info" segments don't really mean much if you're fiddling around with the reservations. The one thing I would be worried about would be if two different underlying airline PNRs both showed confirmed reservations for the same flight on that airline. That would suggest a duplicate booking which would need sorting out,