Hi P K,
I know this thread is answered and I fully agree with Lukas Weigelt most of the way.
I just felt my blog Admin Personalization of your SAP Standard WDA application – How To? (1) might also clear up some of your questions and be helpful to you. I have a variety of the options and haven't had problems with inconsistencies but agree with Lukas that it can be confusing to understand where the change is done. To help us a little bit with that we have mostly disable end-user personalization.
The cookbook you refer to is also excellent for understanding the concept and different options.
Br Jan