Never looked into Dogman much before but this thread's got me properly down a rabbit hole at 2am - cheers for that.
The railroad connection is interesting though. I've spent a fair bit of time poking around crop circle hotspots in Cheshire and you do start to notice these weird geographical clusters that don't make obvious sense on the surface. Old infrastructure corridors - railways, ley lines, ancient drove roads - they keep cropping up (no pun intended) across loads of different phenomena.
Makes me wonder if it's less about the railways themselves and more about what they were built alongside or through. A lot of Victorian-era rail routes were deliberately plotted to follow natural landscape features - valleys, ridgelines, that sort of thing. Could be those same features matter for other reasons we don't fully understand yet.
Also worth considering the mundane explanation: railway corridors are just long, undisturbed stretches of land that wildlife actually uses as movement routes. Could explain some of the sightings statistically.
But then again - some of these reports sound nothing like misidentified wildlife, do they.
Anyone cross-referenced the sighting maps against pre-railway historical records? Curious whether the clustering predates the lines or appears after construction. That gap in the data feels important and I've not seen anyone address it properly yet.