Purdue's OWL on comma usage.
Point three seems relevant here:
- Use a pair of commas in the middle of a sentence to set off clauses, phrases, and words that are not essential to the meaning of the sentence. Use one comma before to indicate the beginning of the pause and one at the end to indicate the end of the pause.
Here are some clues to help you decide whether the sentence element is essential:
If you leave out the clause, phrase, or word, does the sentence still make sense?
Does the clause, phrase, or word interrupt the flow of words in the original sentence?
If you move the element to a different position in the sentence, does the sentence still make sense?
If you answer "yes" to one or more of these questions, then the element in question is nonessential and should be set off with commas.
The sentence "This paper shows strong analysis" still makes sense. 'Yet circuitous' is modifying 'strong,' which is in turn modifying the analysis.
The pacing may seem strange with the comma at the end, but the comma is essential to the intended meaning (subordinating 'yet circuitous' to 'strong').