In addition to referring me to these videos, Wild Birds Unlimited Michigan also referred me to their blog post re White-throated sparrows, which states: "The White-throated Sparrow is medium sized sparrow with brown streaked upper parts, plain gray underparts, and has a conspicuous white throat and yellow lores above the eyes between black-and-white or black-and-tan stripes on the head."
And, so dear reader, it appears that the naturalists I consulted as well as myself made the wrong determination, the bird whom I've been referring to as a Savannah sparrow is indeed a White-throated sparrow!
I'm very grateful to Jennifer DeSelle-Milam for reaching out to me about this which led me to my quest in confirming the bird's identification. And many thanks to Wild Birds Unlimited for their detailed response to my tweet.
I'll end it here as I want to retrace my steps in cyber-space before any fake news is spread re the bird I encountered last Saturday in Central Park!