As per my last post, I'm starting in on data collection for my research project. It's a nice, more-or-less relaxing way to pretend I'm doing something productive over my long weekend. 
For my first sweep of sf/f short stories, I've been going down the award nominee lists, looking for things under 10,000 words that are available online. I've had no problem identifying lots of sf that is clearly sf: "Exhalation," "Evil Robot Monkey," "Little Lost Robot," etc. Some of these fantasy stories are a little trickier, though.
One story that I'm not sure about is James Patrick Kelley's "Don't Stop." It's a modern day ghost story, focused on character, with perhaps some horror. Does it fit my brief of "core fantasy?"
Also worrying because of how it plunges into horror is the modern day supernatural horror story, "The Button Bin" by Mike Allen. Fantasy, horror, slipstream?
And then there's "26 Monkeys, Also the Abyss" by Kij Johnson. Nothing actually precludes an sf reading of this--the monkeys could be doing extra-dimensional travel that they simply do not deign to explain to us. It doesn't *have* to be magic.
My knee-jerk reaction to all three of these is to say that a drop of fantasy makes it fantasy, but all of them have enough ambiguity that I'm not sure they should be included in the core cluster. So far I'm leaving them out and marking them as interesting test cases for the post-training phase. Opinions?
 It's certainly more productive than planning my next tattoo--which I'm pretty sure will happen sooner rather than later, now that I've finalized my plan for my upper back. The final piece finally fell into place over the last week. BWAHAHAHA!