How does that work if you are on an uphill? You will just roll back into the car behind you, unless you mean balance on the clutch? But then how does it work if it is a fairly steep downhill? You will just roll forward anyway if you release the brakes. The other issue is that your brake lights do not light up if you use your handbrake instead. All this to prevent someone getting impatient over a split second delay; it’s just not worth the hassle. You are better of using that effort to observe your surroundings better and not worry about what the person behind you thinks.