Green Glue: 2 tubes, 2 tubes, 3 tubes...

I've placed 2 layers of sheetrock on each side of a staggered wall with 2 tubes GG between each 8x4 sheet (3 tubes for 12x4 sheets). I'm about to place a 3rd layer on each side of the wall and have enough GG to go 3 tubes per 8x4 sheet (4.5 per 12x4).


Would it be beneficial for me to apply 3 tubes per 8x4 sheet on this 3rd and final layer, or would the benefit be so minimal that using the 3rd tube would be a waste of money?



Thanks,

Bob