Can I use the handbrake to help start the car on an upward hill?
No, this must be avoided at all costs. The theory behind this claim is that the handbrake (which locks up the rear wheels) will hold the car in place while the driver finds the friction point on the clutch as he/she gives RPM till the car tries to move forward, at which point the handbrake is released. This technique puts a lot of unnecessary stress on the car’s brake system and clutch disk due to the fact that the car is held in place with the handbrake as the car is simultaneously pulled forward as the clutch is released. The brakes are in a power struggle with the clutch resulting in wear and tear to both systems and ultimately serious damage to both. In a standard car the handbrake is crucial to holding the car in place while it is parked, and the clutch is crucial in operating the car, meaning that damage to these two components are very dangerous.
