Your method will reveal loosening of fasteners, but it doesn't address actual torque values. Suspension components are comprised of consumable wear items which will eventually affect torque values as they degrade. You MUST put a wrench to the bolt to check torque as time goes on.After torquing to spec when I installed my lift, I marked the hardware for the control arms, shocks, trackbars, and end links with a paint marker. At every oil change I visually inspect for looseness and wear.
That said, once you recheck tightness after installation as recommended by the manufacturer, you should be good for a while.