[semken]

Delta does not enforce their own carry-on rules. They have a carry-on model at their ticket-counter and at their gates. If it doesn't fit check it in and pay $25. I did that twice recently and paid $25 each time, although bigger pieces were being carried on both flights, meaning that passengers who ignore Delta's 'rules' not only save money, but don't have to wait at the carousel for their checked luggage

[Butch Cassidy Slept Here]

Those people you see carrying-on bags that should have been checked will get nailed (for bag fees) if they are connecting to a flight which uses regional jet, or commuter prop, equipment. Otherwise, yes, they may get away with it. It's a toss of the dice. Some gate agents and flight attendants will let you carry on the kitchen sink. Others will nail you if you're one millimeter over the allowable dimensions.

[jimworcs]

And therein lies the problem. The sheer arbitrariness of the decision making sets up conflict. People are at the mercy of the mood of a particular staff person. At Delta that is disastrous, because they are known for their toxic attitude to their passengers as it is. It facilitates nasty, arbitrary and inconsistent application of the "rules" in a punitive way.