No no, this one is "all stays within family" type of case. RC code was moved from one place to another and cleaned up. The key point is that if you look at the changes, it "is obvious" they should not influence anything, yet they unexpectedly do. It shows that changing blockchain code is a bit like walking on a minefield. It is also an introduction to the power of new RC stamps mechanism that right after its inception caught such subtle influence that would otherwise most likely never be detected.
I have similar story about ongoing bug with power down (its fix will activate with HF28), or already fixed in v1.27.5, but with wild workaround, problem of strange values on some accounts' properties detected during testing of Balance Tracker app. I might describe them in future articles, since it could be useful case study for people wanting to try their skills on consensus code.