Technically you're supposed to hold on brakes or a hand brake while idle, which makes both points moot. Especially important in clutchless cars or other auto transmissions.

The brakes will hold a slipped clutch and a rear end.

The clutch has an added benefit of you get rear ended and drop it - engine braking is a thing. Not good for the engine, potentially good for your forward bumper when you get reared.

> The clutch has an added benefit of you get rear ended and drop it - engine braking is a thing.

There's no engine breaking when stopped, if the engine is running.

I typically do keep my foot on the brake when stopped in traffic. And I do balance brakes, clutch and throttle when stopped on a hill. But except for stop-and-go traffic, or when getting ready to punch it, using the clutch and brakes together seems pointless.