Odd Child Components Requiring Deletion

[TheImmortalHotDog]

So I've been cleaning up my monstrosity of a dojo, and I wanted to replace a zen room for a hallway because I disliked the DEAD END doorway (really, there should be models with that replaced with a wall). Upon trying to delete said zen room, the box popped up claiming there were some rooms I needed to deconstruct first,  however I don't see why they must be destroyed.

http://imgur.com/a/hyVbf

Rationally, the rooms must be destroyed so they don't float around with no way to access them, however as you can see the entire floor is also accessible by a hallway + T connector, so I don't see the problem? I'm welcome to be corrected but I really have no clue as to why it's not possible.

(PS, I haven't been on these forums in forever, how do you display the entire image and not use a link? It was something with brackets but I forgot.)