Yeah, my child is a perfectionist too and panics in timed tests. So, this is a good way to overcome his fear of being timed while having fun learning a new skill. Not to mention the advantage of whole brain development this skill gives him - using the right side of the brain to visualize the pictures of the abacus and the left side of the brain to come up with the numbers.
Thank you, it is great to listen to a BTDT story!