This doesn't affect me as I use a trolley system and 25l barrels, but I'm intrigued. How does putting plastic balls in your tanks baffle it?
I get that they have to be punctured so they fill with water, but do you have to completely fill the tank with them for it to be effective. My thinking is, that if you don't and they're allowed to move about in the water they just become part of the fluid mass and surely that would mean they're helping very little if at all. And how can you tell if it's working? Do your vans feel different to drive.
As I say I'm genuinely interested in knowing how this works.