Hello blenderheads,
Let me start this post by asking, can drivers be edited via python scripting? 
Once you set a custom property and use it as a variable in a driver, it seems you can’t change the name of that custom property without going back into the driver and change the path (Single Property Type). Preferably, this would be automatic, but since the path is a string I guess it can’t be.
For example: a custom property “FK On” is created on a bone and you set up the drivers, but uh oh, taking the value of FK On to 1 actually turns on IK. It would be simpler if you could just rename this property to “IK On” instead of going into all the drivers and modify them.
I was thinking perhaps a script that goes into all drivers and changes all instances of the string pose.bones[“Some Bone”][“Custom Attr”] to pose.bones[“Some Bone”][“Different Attr”] could get the job done. Any thoughts on this minor problem?