Well i tried this stuff on a problem wall in my control room. I added another two layers of 5/8ths sheetrock to an existing single layer. the glue went between the 2nd and 3rd layer.
So for a week later i can say that this stuff does seem to do what it claims-- and it seems to be increasing as time goes on. Manufacturer says full attenuation in 30 days.
However- it *is* very messy, kinda pricey, and in hindsight is probably better applied thru some other method that Caulk tubes since its closer to a liquid that to caulk.
i'll report back after 30 days to see if, indeed, the cure time is as they say.
alan