Kevin is spot on with making sure you have the correct clutch head driver bit to fit the hardware.
I haven't tried his suggestion about using a "1/4" impact driver", but I have had success using a 1/4" hex drive clutch head bit like those shown in the 1st pic below with one of the 1/4" hex drive mini-ratchets in the 2nd pic. This setup has given me enough torque, plus the ability to add holding pressure down onto the bit to prevent it from riding up out of the screw head to loosening stubborn hardware.
If you want a little different ratchet setup, I have come across the clutch head driver hex bits that include a standard 1/4" square drive socket base that you can torque away on with a larger ratchet to help remove the stubborn hardware with too.
