Well I certainly do NOT need to deal with goatheads or anything even remotely close to them. The only really common tire shredder around my area is the multitudes of broken glass and the wires from really badly worn tires that show up. The flats I get are about 48-48% due to those two and the other 4% due to all the rest of the hazards.
Maybe play with your pressures a bit more to at least minimize the goo drag? Sounds like you're on the way already from the last post.
Oh, and some folks that deal with trash strewn road shoulders would call themselves exceptionally lucky to only have 6 flats in 2 months. I'm just glad I'm not one of them.