If you're talking about the 1972 Test Die Cut article, the first two paragraphs alone have 4 or 5 totally speculative statements presented as fact.
I see nothing but speculation, questions, statements that say it is possible and such. I can't image anyone would take any of that whole write up as anything but speculation. Regardless, who cares, everything is speculation, everyone get over it.
I am fairly certain(speculation warning) that my uncut strips are the sticker version of the 1972 diecut set that Rusty refers to. I believe some of those stickers made it into circulation, we just don't know how yet. There could be many of these in circulation but few collectors pay any attention to diecut and actual oddities of the stickers as there is so much focus on corners, centering and PSA grades.
My proof of that statement was my winning the bandache square cut on ebay. Also, I have found cut "double wackys" in the wild as hardly anyone even knows the copyright is different on those but cut doubles sure don't look PSA gradable so people skip right over them.
Because the 1979 stickers share the same cuts as the 1972 stickers, in most cases, I bet some of the stickers in 1979 test sticker collections were actually from the 1972 sticker release but the 1979 test sticker craze with the unopened pack find has drawn all attention away from the possibility of 1972 test stickers being out there. An interesting oddity is Gadzooka as the 1979 test set sticker is round, it is square cut on my sheet and it neither on a regular 1973 sticker.
Question for everyone: what does the diecutting look like on a #2 Duzn't? The picture in greg's writeup looks bogus, it looks like a 1973 sticker to me.