Agreed. That's my fundamental understanding as well. That is why I am curious why 55s were conceived and built to begin with, as opposed to just churning out 52Ds in ever larger quantities. What are they bringing to the table that the 52D doesn't?Numbers are important too, you can have more ships means more presence and less time in dock. Having 3 52D instead of 2 055 means you can always have a ship out somewhere showing the flag.