These points were addressed. There is not really any minimum age: at the beginning the child simply enjoys having fun with numbers, the more specific methods taught in this course can be started around age 8 years. I also mentioned about Vera Stevens.
The confusion you mention was explained in lesson 9. For a young child teaching should not be by rote – if it is approached as a fun activity it will be accepted gladly. The rigid approach to teaching must go – there is no right or wrong way.