One adopted improvement per person per week

Joyce Wycoff states:

The employees in the Toyota Kentucky plant are innovating at the rate of more than one adopted improvement per person per week.

This number isn't confirmed by Toyota but let's just imagine it's accurate...

The above improvement adoption rate seems pretty average to me, if not a bit slow. However, I've observed that this rate of adoption may be very frightening to an observer.

I need to collect my thoughts on this.