The reason archers shoot over deer is because they don't use good form...

You must bend at the waist and feel the bow string with your nose (bend your neck as well)...If you don't bend your neck then you raise the rear sight and you will shoot high...Just like when shooting a 12 gauge at a turkey and you look up to see if you hit him...

Now...You can't just go get on a roof and practice...Suit up, get in your stand with your harness and practice...This also teaches you where to position your harness so that it doesn't get in your way...

I'd bet that I shoot just about the slowest compound bow on this forum, the angle doesn't bother me one bit, it ain't the speed, it's the form...