i think it is all a bit confusing but here is what i make of it...........i know i have an IRON Man article from 1971 which claims it was the first worlds (but it was aau)..only usa and england and one lifter from jamaica..were there.....
in iron man lifting news from 1973 it mentions this is the 3rd world championships and some IPF info...the ipf came about in 1972-73 and the 1973 worlds was sanctioned jointly by the IPF (first one by the IPF)and the AAU......So i guess they count the first two worlds as sanctioned by the AAU.....it is all a bit confusing but i think this is fairly accurate....