Yep, looked in to quite extensively last year when released. The only claims of anything even close to advertised results were either from brand new people who seemed only to join to push the product, or from people using less than accurate testing procedures.
There are biological processes that break CYA down to ammonia but we have yet to see this done on a consistent basis. Also a problem is that for a heavily over stabilized pool the cost of removing the ammonia afterwards exceeds the cost of replacing water.
The only 100% guaranteed ways to reduce CYA continue to be water replacement or reverse osmosis.