Artie .... i do not have " general rule or ethic " about that topic .
For sure I do " clone " or blend things to make the image more " pleasing " to my eye .... even add canvas if needed , from my POV .
But I have another sensitivity about these things like i.e. you .... I can live easier with things like the thing crossing the legs , like you could . Nothing wrong with your POV about this topic , I just see it different .
For sure it does look better without the stick crossing that leg ....
But people who know the birds leg , being critical photographers with eagle eyes ..... will see the fake leg
.... for sure the majority will not take notice of it .
Another thing is .... images that has been reworked in terms of removal or adding things can never enter big competitions .
Cheers Andreas