After a quick check:  This seems to have started in P8.   Seems to be a different smoothing algorithm, not a different cone. 

The P7 cone renders fine in P7, but both the 7 and 8 cones are droopy
when rendered in 8 with smoothing on.  (The picture shows the 7 cone
rendered both ways.)

I try to use smoothing as little as possible, turning it on via the CR2 only
for the pieces that (1) need it and (2) don't go bonkers when it's on.

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