Lee Loader

Quick question regarding the chain: is there something about the ProDisc's use on, say, a turret or single stage that would make using the chain to prevent double charging superfluous? I often only read that the chain is for the progressives, which i get in that theres alot going on and its easy to miss but wouldnt/couldnt the same be true on a turret?

The chain cannot be used if the turret is rotating. So, it could not be used on either Lee Turret press but could be used on the Auto Breech Lock Pro.