I have shot both ways and most of my bows are set up to shoot straight off the string. I realize that's old school.
There are advantages and disadvantages to a loop, but shooting off the string has worked very well for me. I think it's whatever you prefer and get used to, but shorter bows and longer draws probably benefit themost from a D loop.
I don't see where a properly installed loop would cause any torque. It might by increasing your draw length cause you to impart some torque to the Bow.
Dan