This is so helpful- I run into this a lot too. Half the time I'm sat here fretting "did the artist who made the ref just not know how to draw wings or is this a design choice made on purpose that makes no physical sense?!?!?"

Yes, same. I usually try to make a compromise cuz I'm never sure if it's a design choice or effect of not knowing how they work. If the client is someone close or a mutual I go more accurate way cuz I think it looks just better and I know they will appreciate my freedom choices.