1910 P Lincoln Wheat Penny

You are correct, Kerry, in the direction that forums can take. They are very much a source of information and help.
With that said, if you need answers beyond what is currently known, it may fall on you to break new ice .
I posted pics of my 1943-S fs-101 DDO on a Facebook group a while back. Looking at the photos, one of the members questioned something that he realized about the die. He had to advocate for his observations, and eventually ,the attributors and collecting community as a whole accepted what he saw. Thus the story behind the recent acceptance of the 1943/2 -S cent. That person now owns what was once my coin and considers it the discovery piece.


Go ahead and keep asking questions and researching answers. We might not have them all.

What we are discussing is the heart of Numismatics, which I find to be a very rewarding endeavor. Learning, observation, research, documentation, discussion, and conclusion. It is not so very different from Science.

The images shown by @kbbpll look similar. I'm not personally familiar with the 1910 issues. Do they exhibit Master Die Doubling such that all 1910 coins show this anomalous "S"?

I think it's "something", but not a DDO. You'll have to expand your investigation to other dates and mints, look at hundreds of coins, accumulate some stats, and try to come up with a theory. Not because it's going to have any collector value, but because you enjoy doing it. In my limited poking around, I'm also seeing it on 1911 Proof, as well as 1910 Proof. What about 1910-S or 1911-S? If it's on a master hub or die, why do most coins show a clean well-rounded tail on the S? Is it really on all of them but the strike brings it out more on proofs than circulation strikes? Were they cleaning up the S and caused this? Did it get transferred to a "working master" but not to others? These are the questions that come up for me, but first you have to prove that it's actually "something" and not MD or random PMD that coincidentally happened on multiple coins.

I went through this with Barber dimes a few years ago. Poking around with a microscope I found minuscule doubling and tripling on a couple letters in America. I thought, did I discover a DDO? Turns out it's probably on all of them, just depends on the strike and image quality to see it.

1910 PR
https://coins.ha.com/itm/proof-linc...bnail-071515
1911 PR
https://coins.ha.com/itm/proof-linc...bnail-071515
https://coins.ha.com/itm/proof-linc...bnail-071515
Clearest image of 1911 PR from here, below.
https://coins.ha.com/itm/proof-linc...bnail-071515