So you have decided to plunge into the world of tagging EFO's, how do you score your first finds. Based on my experience looking at more tagged stamps than I can count I would suggest starting with 1384 & 1384a Winter Sunday. This issue has numerous EFO's some of which are very common.
Below are typical normal tagged versions. Nicely shaped block tags fully filled in and reasonably centered.
Below is a version with the block tagging significantly misregistered. The block is shifted to the point where the vertical gap between the blocks is centered on the image. This EFO is very common on both the normal and precancelled versions. In a random sampling you have at least a 25 percent chance of finding one in my experience.
Another fairly common version is where the block tagging shows worn areas where the tagging doesn't get deposited evenly on the stamp.
A block of 4 with misregistered tagging and showing worn areas.
The following varieties are less common but are out there.
Block tagging is misregistered both horizontally and vertically.
Block tagging mat worn to the point only the edges get printed.
I have been creating these posts to show collectors the fascinating aspects associated with tagging. I have found many collectors know little about this area of the hobby and view it as a specially area. I don't claim to be an expert and just want to demonstrate you don't have to be an expert to pursue this area of the hobby. A small investment in a battery operated SW UV lamp and away you go.