That's weird, I assume the 72 stamped on the seat lug refers to 1972. Mine has that also and is a Brigadier, but is totally different. I have an "Royal" with the 72 stamping that is a butted 531 frame with full dura ace and a Crane RD. There doesn't seem to be any pattern to their production, to me anyway.
Looks like you got your friend a good bike at any rate!
John