Two good possibilities, I think--and I continue to look....
A telephone coin was one of my own guesses, but I have yet to find any evidence. I've also thought maybe it was fare for a streetcar, but again, I've found no evidence.
The collapsing of the 20h and 50h denominations into a single coin as a cost savings measure. It hadn't occurred to me. But now that you've mentioned it, I agree that it's a good, educated guess. I see that production of the 20h suffered some kind of hiccough about 1933, and production of the 50h seemed to end altogether with the 1931 issue. (But it's also true that Czech coin production in general was spotty during the tough times of the '30s.)
The distinctive look of the 25h might argue that its designer was assuming the coin would circulate with the similarly sized 20h and 50h, and needed a different look to forestall confusion...but I guess that might be true even if the concurrent circulation was only a brief thing, to be followed by the retirement of the 20h and 50h.
The idea of substituting a 25h coin for the 20h and 50h does gain a little additional plausibility (in my mind, anyway) because both American and French influence were alive in the Czechoslovakia of the time, and both the U.S. and France were--at that time--confirmed members of the "25-subunit club."
So thanks for the ideas. If anyone else has an idea or finds something, please let us know. In the meantime, I'll continue to look and will do likewise. I've contacted a Czech numismatic society but have never heard back.
I wonder...maybe the 1932-3 25h has some sort of deflationary inspiration, as with the 1932 4-reichspfennig. Oh well. Fun!
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