Joliet Jake

@N.E. Body I thought of it like: A style may be considered in or out of fashion; or a person may be in or out of love with something/someone. Or if you're really interested in something/someone, you're "all in." I realize none of this is particularly helpful, but it's how I rationalized it anyway. :)

@OboeSteph Same here! But it was fun learning about the phrase. Now that we know it, I bet we'll notice it popping up everywhere. :)