The challenge of too much flexibility.The IOD standard - the basis for DICOM - allows for customization of data collection forms in ways that make it hard to recombine the data later. It's a little too flexible. Think about this for a little bit. Have we ever tried to combine data - say spreadsheets from different people - and had to do a lot of manipulations to combine them? If we don't have a work example, think of how such a challenge might come up.