This has been discussed before at least once.
I seem to remember ( though cannot find ) the basic reason
given was that we ( meaning the Monastery, not the secret
cabal ) did not want somebody to get the root node approved
and then modify it after the fact. This, it was thought,
could lead to confusion and abuse.
in reply to Point of No Return (a.k.a. The Dangers of
I do like the idea of being able to modify it until it is
approved though, as mentioned in the linked node above.
I wonder if Fearless Leader could implement that.