What feels like the cranks skipping a beat

I'm with Smallfurry.

The lockring is only 'unnecessary' if the torque applied to the ring during a skid or other sudden deceleration of the rear wheel is less than that with which the ring was fitted - ie. YOU STILL NEED THE LOCKRING.

the statement of "the lockring is now unecessary" doesn't feature in all the rotafix tutorials.