Adjusted probability logic.  Cleared out a lot of old Player code (and subclass code) that wasn't doing anything.  Changed player loading files (again, to avoid the code that was just going nowhere).  Now the issues are just with overall probability being very very very small most of the time - possibly due to rounding errors?
Adjusted PlayerTests, which had apparently been half converted to using integers (also, one of the test values was off - we set skill to 0.5 and then expected it to be 0.6 - fixed that too).  Also, I hadn't correctly fixed the bad player file, so it wasn't throwing the error it was supposed to (because it wasn't wrong).  Fixed that too.