Split it into 2 segments so that the non-original segment (i.e. the one I move into position when actually performing the split) was cutting through a curtain wall with mullions for which I had assigned special profiles, which on the other hand were made from a detail items.
Sounds pretty normal, right?
So when cut through the original segment of the split section the mullions' profiles display fine, but not when cut through the non-original segment of the section. Instead they display there simplified, as in a coarse view. What gives?