According to this help file Work with table driven iFeatures
1. In a part file with a table-driven iFeature, right-click the table icon, and then click Edit Table.
However, in my part file (or any other) I do not get this option 'Edit Table' when I right-click on the table. Being able to
edit the table from the part file is important. I can always edit the ide file and re-insert the iFeature but that is definitely
counterproductive...
See attached image