bonzaman,
Yes, your procedure is as I remember it. Glad you mention that only a
gentle tap is required to resurrect a stuck impulse mechanism. Many Tiger Moths bear scars in the area of the right magneto coupling as a result of being assaulted vigorously by the front cockpit joystick or similar object.
In fact a gentle tap with a 20 cent coin on the magneto coupling collar is all that is required to release the mechanism and is rewarded by an audible "click". Like cracking a safe!
Own a Tiger Moth!!Lucky ******!! Happy flying.