And my point is that the statistical variation is an anomaly based on the low numbers of Catholics.
A Catholic Chief of Chaplain will happen roughly 1 out of 2 or 1 out of 3 times. This will because Catholics should have 300 of the chaplain slots.
When a Catholic is promotable, the board has to consider the fact that catholic priests are under-represented and that a fully qualified priest almost always will go forward.
As I’ve pointed out, the ELCA is one of the few mainlines that even bother to send chaplains: Methodists, presbyterians, UCC, and CofCDisciples each have a few chaplains. To my knowledge, though, ELCA and Presbys are the only denominations to have the Chief’s job recently.
I don't know why you keep going back to the RC's. They are not the only liberal denomination that has had a chief of chaplains. The article is arguing that the it is the denomination of the chief of chaplains that is the main factor.