O&S(meme) - terminology is the key

I suspect this is "pixels" as someone - probably from one of the "mounted" regiments in the BAOR - has got more than a little fed up of the references to "Thomas the Tank" as the shorthand for Thomas the Tank Engine". Made me smile, as I also prefer the correct / full terminology whenever possible. However, the source locomotive isn't "Thomas" but something quite different.
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not my image : fair use & public education