Rich,
I've also seen leaf spring set-ups get cocked. And loosening all the bolts and straightening things back up is what to do. The first time I saw a twisted up leaf assy. I was worried as it was a 4 wheel drive Toyota that I bought cheep, a farm truck. The young guy who did my alignment, who messed w/ off-road 4 wheel drive trucks, acted like it was nothing. He told me to do just what you said, Rich, take it all loose and straighten it up again. I did and it was just fine. A shocking damn thing to see if it's your first time and it's your ride. LOL It comes from regular vibration and a little beating on occasion. LOL I suppose some good either self-lockers or good lock washers would be in order if that's the case, and regular checking.