The threading definitely helped with the script itself, but the GPS is still only refreshing the values 1/sec, i.e. if I sleep for .1 seconds, the same speed is reported 10 times. Is there any way to truly confirm if the rate changes are "sticking"? None of the commands report errors unless I do something explicitly wrong (e.g. if I try echoing to the serial port while gpsd is running, or if I try using the gpsd command when it's not running).