Harambulus,
To me, "whiteknuckling" it is a description of allowing your Addictive Voice to engage you in a struggle. When you allow yourself to be so engaged, you are empowering the AV to affect your behavior. Continuing such a struggle only tires you, and your AV has time.
Instead of struggling, just let go. Don't argue any more. Let the AV/Beast have their conversations without you. It really is only "noise" and need not be paid attention to. After awhile, the noise is not so loud any more, and may even seem to disappear for periods of time.
As I've said before, your Big Plan is not a "thesis" for presentation to the AV/Beast for examination and argument. It is a statement of self-identity as a non-drinker or non-substance-user. It is who you are.
These are my thoughts and definitions. I'm sure the book explains it much better than I do. Get the book and read it. Terminally Unique will give you, or has given you the titles and references.
Personally, I think "whiteknuckling" it is a ridiculous concept and one I would never engage in. It implies a struggle that cannot be sustained, and really is just your Addictive Voice giving you a pass to go back to being a drinker/drug user. You'll hear this term a lot with people who have relapsed and continue to struggle. It is not an AVRT concept at all.