I guess I was able to imagine the 'cant' but not why. I'm right-handed and right-eyed. Covering my right eye, I was able to sight the pistol in either hand without 'canting'. Hell, maybe I'm 'ambi-eyed'! I sighted the pistol in each hand with both eyes open. When in my left hand, I was left-eyed. In the right hand, I was right-eyed. So, I got out another 1911 and tried two at once, both eyes open of course. I saw right away that I can't actually sight but one at a time. I think its physically impossible to sight both at the same time, but you can point both at the same time, which must be how two-gun shooters do it. But even so, neither one needs to be canted, although they both would be turned inward so the POIs would be the same at the target range (probably no more than 45'). This would take some practice, and I'm pretty sure the old man at the range would have a heart attack if he caught me shooting two pistols. But I do practice frequently shooting with the left hand just in case I ever get the chance to try it.