How mature is your process?
Productivity is about making things happen when they're supposed to happen. It's about keeping the train on track and on time. The myriad number of ways to do this can boggle the mind. As we look at productivity methods and methodologies, we should take into consideration their "maturity" for lack of a better term.
Any good process must be:
Repeatable
Understandable
Explainable
Adaptable
If your process, whether adopting one from an expert or implementing your own, does not meet these basic measures then it's maturity is questionable as is it's ultimate success for you. As your process grows and changes, allow it to mature to become a powerful ally for you rather than just something too big for it's britches.