Dave,
Sorry to see your Rover past it's axles in what looks like talcum powder. That is going to be real "fun" getting out of.
HEY!!! New Idea for FRC games
Who can get unstuck from the "muck" (or whatever else they can scheme up) the fastest and most innovative way!
I can't comment on the shirt, I'm new to this world of wonder and don't seem to have the inside knowledge needed. How about posting a Pic.
Good luck to NASA on a successful extraction!