Hi Nicola,
good question, that is because the eILCD format basically mimics GaBi, where you make a physical copy of every process that is part of a plan, and can link this process in the plan to quite many things, and thus possibly, the same original process exists multiple time in the plan, as redundant but then potentially modified instance. It can have very different links and be otherwise different than the original process in the database.
Makeing a physical copy of the process does not affect the integrity although it is certainly not elegant, but maybe you agree that this comes from the format.
Best wishes,
Andreas