Short answer: you can't! You, my friend, are ALL signal *g*.
More specifically, since all we have is an upper bound on how many of your XP come from writeups, and that upper bound is actually higher than your total XP, you lie on the other side of the boundary condition where the two are equal.
I conclude by this that you don't vote much? Either that or you are the victim of some VERY bad luck with Tim's random number generator :)
Spud Zeppelin * firstname.lastname@example.org