Has anyone tried the glen doman baby Flashcards. Does it really work to teach baby math at a young age?

I used my own DIY flash cards, encoclypedia, math and english for my baby no.1 when she turned 5 months old. I feel it is great for bonding and instill general knowledge to babies. However, to make sure it is successful, you must really commit your effort and time to do it daily. My baby did recognise species of dogs, world famous drawings, and etc. through the flash cards. However, due to work commitment when my baby is 1 year old, I do not have time to do the flash cards. When my baby was 2 years old, I tried to test some of the cards and she can't remember. But overall, I feel my girl's memory is quite good to remember some stuff. For me, I think this method is good to stimulate right brain of young babies (before 6 years old), thus it is a good investment of time and effort. For my subsequent babies, I am more favor of montessori approaches which I think it suit my teaching styles better.