Dear Eric,

After a second reading of the TUPLE class's code, I now fully agree with you.
My first answer was more related to the objects tool implementation.
Indeed it display only the attributes, except for particular types such as SPECIAL and TUPLE, where we display the items. 
However I agree we could/should display the object_comparison value, since in the tuple's context, it could be assimilated to a field.

This will be fixed soon.