It's buggy and broken, and if the code actually were to stick around, I'd have to change it somewhat for sparse/dense API adjustments. Plus it seems to make fuzzers cry fairly regularly, and not actually with good reason, either.
Created attachment 550868 [details] [diff] [review]
Interestingly, it seems no tests needed to be changed for this removal. I guess people have been doing a good job at discouraging addition of split-using tests...
Created attachment 550880 [details] [diff] [review]
v2, with less dumb