definately not foolproof (Score 1)

besides the earlier stated ways of getting by this device...such as putting a device inbetween the mouse and computer to capture the signal and store it for another person a program(a basic trojan horse could do the job) could capture signals from the mouse so that it could be stored in another device that could stored in a "mouse lock pick" if you will, which could store many and could also a brute force approach