Originally Posted by
MSPeconomist
I also find the rule very strange in that the total weight loaded onto the aircraft is the same regardless of whether someone carries or checks the bag. I guess the balance part could matter if it's preferable to have weight in the cabin rather than in the belly of the aircraft. However, I'm inclined that the real issue if space (volume) for cargo rather than weight per see.
In my personal, limited experience with payload optimized flights, every time I’ve had a mainline flight where gate checks had to be minimized, it was all about keeping weight down. I’ve never had a mainline flight where cargo bin space was an issue. “Bulking out” is only something I’ve seen on Delta Connection’s smaller bins. Im sure there are some markets with big cargo loads like Alaska with fish or northern South America with produce where space might be a limiting factor.