I see it being like NIN's Kassatsu or something like that. Something like : Air Anchor -> Reassemble -> Air Anchor CD resets and is changed to Chain Saw.
So instead of pressing reassemble on CD with Drill, there would be a little more planning to do.
It might become something like : Air Anchor -> Reassemble -> Chain Saw -> Reassemble -> Drill.
Edit: After rewatching: chainsaw gives at least 20 battery gauge, just like air anchor. So yeah, it is probably something like that.