adjustable Dual Flush valve

Hi, we are evaluating a dual flush valve for WC, which give us 6 & 9 Litres per flush(adjustable) which aggregates to 7 litres per flush, our project requirement is 3.023 Litres per flush(0.8 gpf), since this flush valve can be adjusted we can adjust it suitably so that it yields flush rate closer to our requirement(if not exact,) would this methodology be accepted by USGBC. The flush valve model in question is : http://www.grohe.com/ie/5636/search/search-result/product-details/?product=38519-D024&color=000&material=38519000