As per your book: Renaming the object doesnot update all the scripts which are using shared object repository.
Today I tested and found the scripts are updated. For example:
1. I created a shared or.
2. New test-> associated shared or.
3. add some steps with objects which are in shared or.
4. save the test.
5. New test-> OR manager-> rename the objects of shared or which are used in previious script. Save shared OR (donot save the blank test)
6. Open the test (which is saved at step 4)
Result-> script is updated with new object names.