For each duplicate attribute id an error »ID "some" has already been defined« is reported. I think this is sufficient, maybe the text could be a little bit similar to what AHF itself reports for duplicate IDs.
The additional error »first occurrence of ID "some"« is misleading as it is raised for all but the first occurrence of the duplicate attribute and therefore just fills the error view.
My suggestion:
- create an INFO entry for the real first occurrence of this id value (unless this is too time-consuming)
- or remove that error
Thanks!