I got a "skinny" audit about ten years ago, all they wanted was proof of mileage. Fortunately, I have notebooks where I record at least an outline of what I do each day (sometimes more detailed if it's for a job where I need to invoice for time and expenses) and the first note is the truck mileage before I even start the engine. My office is at home, so I don't have any non-qualifying commute-to-work miles. For the audit I spent an hour photocopying that year's notebook, which I mailed to them. Not too long after I got a "Thank you very much" letter, and the audit was over. I suspect that if I hadn't the detailed notes that I would have been in for a full audit.
You never change things by fighting the existing reality. To change something, build a new model that makes the old model obsolete. R. Buckminster Fuller