"Calling cues" during pig slinging? I think not. MORE people, particularly on the rail, makes an operation LESS safe. My policy is only ONE person (the Head Flyman) runs the Lockrail and calls instructions to the Loaders during Ins and Outs. During Performances, no more than the number of simultaneous moving lines, which will rarely be more than three on any theatrical show.
I agree with you totally, except for the fact that many shows require many moving linesets at once. We often have 8 or more linesets moving in a cue. Just getting three sets of legs up so that scenery can move in addition to drops and other scenery can add up really fast.