Dave,
I don't think the problem is so much too much petroleum jelly, but not enough dry cotton. I made a run of balls out of 3-x size cotton by rubbing the jelly on the outside of the ball, but not all the way through it. I stuffed them into a match safe and went hiking. Once in the field, I split the ball open, pulled the dry fibers out (I realize that this is not consistent with a one handed ignition), and placed it on a piece of bark. I was comparing a BM, and a Spark-Lite. Both ignited the dry fibers first, second, or third attempt (and did so in future tests as well). I also used the back of a knife blade (AUS 6, I believe) on the BM to create sparks. I think the trick is to see that the dry cotton acts as a wick and the saturated cotton makes the jelly available to those wicks.
FWIW,
Biscuits