Sorry I don't know more, so I'm throwing it out to the collective wisdom: what's going on with Rinku Singh?
Last year, he threw in the Gulf Coast League most of the year, earning a late callup to State College (where he did fine in 1 appearance, 2IP 1H 1K 0BB). We know that he spent the winter in Australia, desperately trying to make up for 18 years of knowing nothing whatsoever about baseball. Then he went to the Dominican Summer League (where, incidentally, the Pirates' affiliate is leading their division) and pitched well again (3 relief appearances, 11IP 7H 3ER 3BB 7K). Now he's back in the GCL, having one appearance (4IP 1H 0BB 5K).
Now, I assume that this has much more to do with roster management and a pitcher squeeze at State College than any hard judgement about Rinku's future, but still: seems to me the guy's done everything anyone could have expected, and his numbers the last 2 years have been outstanding. He'll be 23 in 6 weeks, so he's starting to age out of the low minors (I'm willing to grant him a mulligan year or two due to unfamiliarity, but a 22-y.o. dominating the GCL doesn't tell you much because he's physically so advanced relative to most of the competition). Do we think he's a few strong appearances away from a promotion? Do we think it makes sense to slow-walk him? Do we simply think that a guy with a 33:11 K:BB and a 7.88 K/9 over the last two seasons has no future at all?