My interpretation is that it does add the bonus on any morale bonus.
"A courageous weapon fortifies the wielder's courage and morale in battle. The wielder gains a morale bonus on saving throws against fear equal to the weapon's enhancement bonus. In addition, any morale bonus the wielder gains from any other source is increased by half the weapon's enhancement bonus (minimum 1)."
I think that it's pretty clear.
Like I say, if there is no official statement, go by RAW or talk the RAI in your table, don't try to be the next mesias and make your words the ultimate truth.
Now you can continue twisting the words like lawyers, these are my 2cts.