Add competencies in talent profile from performance document

Summary:

Hi all,

we created a performance document in which both employee and manager evaluate the competencies of the employee's job profile.
We set up the document template so that both the manager can add and delete competencies during the evaluation phase.

Once the performance document is completed however both can still add and delete competencies.
Is it possible to change this behavior? we would like manager and employee to be able to add/delete competencies only as long as the performance document is open. Once completed neither the manager nor the employee should be able to do this.

Thank you,