Okay, the title of this post is actually complete crap, because it's not about "cheating" and I'm personally not "on a diet". It's more nuanced than than that. It's about when to indulge a desire for something you know may be bad for you, but you really do want to eat it anyway.

For those moments, this pdf link is absolutely priceless!  *grin*

Whole9′s Guide to Nutritional Off-Roading