Will Hard Reset Lumia 920 causes it to brick?

Charge it enough to show the spinning wheels.
Start the NCS, follow the steps, but do not plug the phone in yet.
When the NCS throws an error and ask you to reset the phone with Volume Down and Power and connect. Do that and connect the phone immediately after the short vibration.
Make sure drivers are installed correctly. You might have to redo the process again if Windows takes its time to recognize the device and install the driver.
After that flashing took about 3~5 minutes.

Yup.

It shouldn't but it can, not always, but sometimes.