Well, you and I have both been at the study of 'internal' for more then a few days....
I haven't heard you explain how 'internal' resists a push any differently than modern athletics would. Yet, you're sure that it is different...
You generally would not resist it, you would float your opponent, or put your opponent in a hole. This is what the aikido waza look like to me. You get underneath or unbalance your partner, then put them into a direction they are weak.
Martially its better to not have force on force on the same angle unless you can generate more than the other guy.
As for athletics, it is not my experience that most people can innately do a ground path. Sure they can do it once they are shown, but that isn't their initial reaction.