What's he doing here?

[will_f]

Dumb question: I am trying to recreate Victor's sideways walking machine, and it looks similar, but the target bones will not move.
Is there a setting on the target bone constriction that I missed?
Everything looks the same, I have the position control bones referring to the correct targets, but the targets themselves won't move.

Update: Never mind, I got it fixed. Not sure what I did wrong, but I deleted, then recreated, the target bones. It works fine now.

Neat.