I cant the pistol one handed and often suggest or teach this method which very often cures a lot of issues for many shooters. Canting may be natural in rollouts and in improvised shooting positions which we may often find ourselves in. Knowing POA/POI is minor in regards to most handguns within normal handgun distances. Since we often may find ourselves shooting with a canted weapon due to our situation, getting used to shooting this way becomes a part of training. Why so anal about canting a pistol when we do it all the time with our rifles? Heck we train and do it all the time with our rifles, where this becomes more problematic due to the normal offset on the rifle. Also for our guys when using a shield it is almost impossible to shoot without canting the weapon if you want any semblance of a proper sight alignment / sight picture, so knowing how to do the technique is a must, at least for us.
Canting is generally a more natural body position when firing one handed. Just make a fist and extend either arm and see where your body naturally ends up and in which body position you have more power and control with your arm extended. Sometimes it helps to close your eyes when you punch, or extend out, so as not to visually influence your position. This is about the position where you may feel the most comfortable holding the pistol one handed. For myself I have a good 30-35* or so cant from vertical. I find that for myself, it takes quite a bit of muscle tension in my shoulder and arm, to maintain a vertical hold on the weapon, due to fighting my body’s natural position.
Using a combat isosceles, I will slightly widen my natural stance, and drop a leg slightly farther backward, lowering my center of gravity a bit. I will keep the weapon as centered to my mid line as possible and not favor one side or another even though I am shooting with one hand (no bladed target stance). From there I will punch out the weapon and let it stop at full extension in whatever position my body will normally end up in, generally 30-35*. Another small thing that I do, is that I will not cant my head in the same direction as the pistol, which you may see people do. I will keep my head as vertical as possible and not cant my head with the pistol. This just tends to help me stay better balanced. Of course if we go to many alternate shooting positions, keeping the head vertical may not be an option.
Shooting one handed, I personally lock out my elbow at full extension. I try to drive the recoil, directly as possible with one hand, into my body centerline, as opposed to bending an elbow to help absorb the recoil. After much practice I find that since recoil management is more difficult one handed, I strive for more consistency in where the recoil goes, or where my pistol ends up after the recoil. By locking out my elbow I find greater consistency in where the pistol ends up post recoil. In being more consistent on where the weapon ends up after the recoil, I am able to more quickly return the weapon to the same firing position with greater consistency every time, which increases my speed and accuracy of follow up shots. Again the lockout is just a personal preference thing for me.
To each their own and I have heard most of the arguments either way. I will say that if someone does something extremely well one way and just cannot perform another method, trying to train it out of them, is not always a good thing. Of course we want to give a new technique a fair chance at success, but there are times when it may not be in the best interest to mess with a good thing, but rather promote that good thing and make what works for an individual, even better. 
