...which it sounds like you do when you push off. But I've found that in order to actually back under power you have to start the prop spinning at idle and let it build a bit at idle, then you can add a bit more power but be judicious. I recommend experimenting at a dock where it's not..uh, critical at the moment. Learn the distance you need, play with winds across if you can find the right dock. It's always worked for me on several boats but it's hard to say.. Best of luck.