I don’t know it is true or not.
Because I already made my 3 digit system (It takes a lot of time to make) and never get any good results with that.
Even with a lot of practice.
And even I can’t do 80 numbers in 60 sec.
I think it takes time to achieve better results.
In IAM, I memorize 240+ numbers (In my first attempt) by 2 digit system but sadly to say that by 3 digit system I never crossed the boundary of 150 .
Even if I forgot the 2 digit number, I can easily find the word in 100 digit word list.
But If I forgot 3 digit system words in recalling time , It was hell for me to find the correct word. (I wonder how andrea muzii can recall the number fastly if he forgot )
And I think pao system is better this time for me to memorize numbers faster.