I agree with all of the above , i am a bloke who likes to cut costs , i've tried it all , low flows , by passes , you name it i tried it , then i tried banging up the flow , it worked a treat , i found the time you save on each house far outweighs the water use , more water , less time taken , time is money , i bet if you try it then you wont be worse off , if you work 25% faster and use 25% more water what have you lost ?
Nothing , you just get to go home earlier , or refill and work longer earning more !
Rich