Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense. (Prince Gautama Siddharta)
I've always been an advocate of applying common sense to one's life. It is usually the simple and eloquent solutions that work best. One thing I believe you should consider is the best way to invest your time. As with any investment, you want to get the best bang for your buck. Does the benefit associated with an activity outweigh its costs? What is the risk you are willing to bear?
For a large-scale complex project, complete traceability may be warranted. For a small budget, low risk project; is the same level of traceability required? I would suggest not.
Having a well defined methodology with structured processes and procedures is excellent. But you must be willing to be flexible when the situation warrants it. What works well under one set of circumstances will not necessarily work well in another. Use your common sense to guide you to make the optimal choice.