- type changed from defect (bug) to enhancement
- summary changed from capability inconsistency to add create_posts capability
Okay, managed a few minutes today to take a fresh look. All my issues were caused by trying to remove the Add New menu item from my custom post prior to any changes I made to Wordpress code. In the admin_menu hook, I used
unset($submenu['edit.php?post_type=my_post_type'][10]);
to remove it. This is what caused item 2 since initially the submenu had two items and was reduced to one item which was removed because it was the same as its $parent thus leading to an inconsistent state of $submenu. Having a create_post capability in place would resolve this. Item 1 is invalid.
I'm changing the summary and marking this as an enhancement request.
The create_posts capability would be used to determine if someone has the ability to Add New.