Since K BROOKS was unsure about packing his 360 for the train ride, I suggested he just bring the detachable HDD-he doesn't have a Memory Unit. I could transfer my profile & PDZ data from my HDD to my Memory Unit, plug his HDD into my console along with my Memory Unit, and then we could continue the campaign old school splitscreen styles. Wrong. PDZ data cannot be transferred between devices.
So while we were able to play splitscreen co-op using both of our profiles, none of my PDZ data was on hand, meaning that I headed into the final battle with a P9P and came out with "0" (how ironic) gamer points. The frustrating solution was to transfer K BROOKS's profile onto the Memory Unit, reattach my HDD, and beat the game again, so that we both received the points. Unfortunately, the gamer points problem persisted when we entered the "Combat Arena."
No big deal if you're not a sucker for gamer points, but this could pose a problem if you ever need to move the data to a different memory device. Let's hope Rare takes notice and issues a patch, and that other developers follow suit. [Note: we have not experienced nontransferable game data with any other 360 titles. Have you?]
Other Xbox 360 annoyances: 001, 002, 003, 004, 005, 006, 007, 008, 009, 010, 011, 012
Xbox 360 delights: 001, 002, 003, 004, 005, 006, 007