Editor presentation bahavior is different when add presentation

Hello all,

I found this inconsistent behavior with editor presentation.
Can anyone please have a look and let me know if I am missing something?

I am using the sample Money that matters project and editing editor presentation on eclipse client.
When you add presentation to a header which is already shared, you see 2 different behaviors for [replace this instance] option.

- For [com.ibm.team.workitem.editor.task]
  Header section [com.ibm.team.workitem.header.simple] is shared
  Click on [Add Presentation]
  [Replace this instance of the shared section with a duplicate unshared section] has 1 field that let you enter section ID.
  [New unshared section ID]


- For [com.ibm.team.apt.editor.story]
  Header section [com.ibm.team.workitem.header.simple] is shared
  Click on [Add Presentation]
  [Replace this instance of the shared section with a duplicate unshared section] has 1 field that let you enter section ID.
  [New unshared section ID]
  [New unshared tab ID]


Is this an expected behavior?
I don't understand why the same header section shows 2 different options for adding a presentation to it.
Any information you can provide me would be greatly appreciated.