I believe it also depends on what you have the rest of your team set at as this makes a difference ex:
15,13,12,8,7,5,2,0
Compared to
3,2,1,0,0,0,0,0
I believe if your doing the 2nd example and only have 3 players a set distro then I believe 0 is more of a "flow" and if the first example he might just be in the right spot at the right time. As distro isn't 100% followed. I'd say reguardless of what distro settings I wouldn't be to alarmed how many minutes is he playing too could be a factor, if he's playing 15 mpg and 1 shot a game would be perfectly normal with a 0 distro.
Hopefully someone can do a better job at confirming