Well I think that conflates two types of situations.
A typical misperforation (which I'd consider as any type of deviation from a standard perforation) - is the perforation shift. This scenario is fairly common and slices and dices stamps in every possible conceived way, effectively altering the placement of images on the stamp).
Unpunched examples
https://www.ebay.com/itm/missing-st...323310420026https://www.ebay.com/itm/US-AIRMAIL...312366957678The blind perfs, albeit are new to me, I can understand the appeal. I'd label it as such in an album, and if I were to sell it, because I'd think it is worth celebrating it's real state, rather than concealing it as an imperf.