Testing timing chain stretch via crankshaft/distributor rotation?

I searched but couldn't find the post regarding a technique where rotating the crankshaft (at the harmonic balancer) with a breaker bar and watching the distributor rotor one could gauge if the timing chain had too much slack.

Does that ring a bell with anyone?

Thanks,

John V.

I'm sure it's possible by moving the crank bolt back and forth while watching the distributor rotor.