Why Changing The Order Works (Continued): If two or more system extensions patch the same trap, they can both be altering this data, and the results can be deadly. By rearranging the system extensions, sometimes you can set it up such that a finicky cdev sees the data before some other cdev changes it. Because of the way the trap patching works, the first system extension loaded sees the data LAST, and the last one loaded sees it FIRST.