This is not true. OSX locks down the FireWire ports to protect system memory. I am not sure exactly how this works but I believe it's firmware/driver dependent

This is not true. OSX locks down the FireWire ports to protect system memory. I am not sure exactly how this works but I believe it's firmware/driver dependent and Windows usually lacks the drivers to force the firmware into a protected mode. FireWire having direct access to the system ram is not a requirement of the 1.0 spec, it's a stupid implemention decision by chip designers.