Ideally, if your string arm is relaxed, and if you are pulling with your back muscles, your string hand should follow the angle of the string and not torque. You should be able to cant the bow, with or without bending your body with the cant, and your string hand should follow whatever cant your bow hand puts on the bow.
That is what you should work on doing, but it is not an easy thing to do. You can also shoot fairly well if you do it backwards. In other words, set your string hand at a certain cant and relax your bow hand enough that you can see where the bow wants to go.
I also like to shoot with the string blur just visible on the outside of my eye, and accomplish that without torqueing the bow by alternatively relaxing my bow hand and rotating my string hand until everything is in balance and the string is where I want it. This is not as desirable as if I could just totally relax my string hand so it would follow the angle set by my bow hand, but I have a hard time doing that.
In answer to your other question, I think that if you truly bent your body to the same angle as the cant, you would never solve your first problem, which is getting the string blur out of the center of your eye. I think that once you establish a good shooting position with the string blur to the side of your eye, it would probably be a good idea to maintain that allignment by bending your body with your cant so the string blur always appears in the same position. As a practical matter, I find that I'm only using extreme cants at short ranges, so as long as I use good form the arrow seems to go pretty much where I'm looking.