"But I'm a little baffled by the argument that the creator of an "original" work automatically does more than the star of a revival"
The role in a revival has already been tested and they know enough that the character and the songs are going to work. Patti already had a template. They knew the jokes worked, they knew that "Blow Gabriel Blow" and "Anything Goes" were audience pleasers. They knew that "Friendship" worked. The revival of Anything Goes was what was expected. It wasn't testing any new ground in tone or style like the revival of Cabaret did.
When you have a song like "Moments in the Woods" you don't know if that song is going to work or not until it gets up several times in front of audiences. Think how much material is cut or changed from any given show in out of town tryouts because audiences weren't engaged.
Joanna was creating a new character and decisions had to be made. Is she too mousy, should she be more bossy? Who is the person? Will the audience be engaged with the character? She didn't have a template to work from.
If anyone ever tells you that you put too much Parmesan cheese on your pasta, stop talking to them. You don't need that kind of negativity in your life.