Looking at quite a few Pogliaghi's from this time period two thoughts come to mind. Sante was starting to get pretty old by the mid 70's and was probably bringing in more and more builders to meet the demands of his business. perhaps they were given some freedom with materials and cut out selection. Also, this bike is fairly close in age when Pog's went from the long point lugs with small diamond cutouts (usually) to the larger quasi hart shapes that are on newer bikes. They might have been doing some creative R&D on cut outs and fork crowns to see what is popular when they made this bike.
Just some thoughts from a Pogliaghi fan,
Brian Fessenden
Orinda, CA