What Do My Favorite Poem and My First Colonoscopy Have in Common?

When I was a senior in high school, an English teacher introduced the class to a poem that immediately took up permanent residence in my head: “For Once, Then, Something,” by Robert Frost.
It goes like this:
Others taunt me with having knelt at well-curbs
Always wrong to the light, so never seeing
Deeper down in the well than…