The following are examples from Bryan Garner's Modern American Usage Style Manual. In the phrasal-adjectives section, he doesn't explain why the first example below is separated by a comma and why the remaining examples are not. Does anybody know why this is? Please, no recasts, as I am trying to understand this. Why a comma here? •blue-blood, country-club Republicans But no commas here? Wouldn't a comma after approved, latency, old, day, and monitored aid readability in these—yes or no? Would you include those commas below? •county-approved billboard-siting restriction •long-latency occupational-disease cases •13-year-old court-ordered busing plan •24-hour-a-day doctor-supervised care •24-hour-a-day in-house-monitored doctor-supervised care Thank you.