dunno. Seems to work using Poser Default Props as parent, but, IIRC, not always with other objects as parent.

Really don't recall specifics, but may have been other factors in play when parenting to a non-Poser default prop did not work in past (such as daisy-chained parenting perhaps? Deleted Parent prop may itself have been parented to another obj, yielding the unexpected results).

btw - most frequently use this parenting trick to Scale, Rot, and Trans the entire lighting setup all at once.