The J&J spec is to delete persons from the person table, if they have more than a single observation period with a changed gender. This is the behavior I feel should be repudiated.
The J&J spec is internally inconsistant, in that it conflicts with another of their person table key conventions:
• If the person’s demographics change during the period of analysis, the last known record is used.
I feel this is the key convention should be applied to the gender demographic,
I agree with your recommendation about gender identity appropriately being in the observation table. One must note, however, that only if one does not follow the J&J spec, will there be a person entry, or any observation table entries for such an individual.