It is a pretty interesting question. I am a lefty, and like a lot of southpaws, we just sort of grow up semi-ambidextrous. I throw a baseball left handed, but a football right. I switch hit at the plate with pretty equal success. I shoot a rifle right handed, but always wanted to shoot a bow right. I am right eye dominant tho, so I had to switch. When I was younger, golfed lefty, then switched to righty cause I bought a set of used clubs that were right. Suck about equally either hand there. Spent some time with my left arm in a cast. Could write pretty neatly as a righty. I can pound a nail just as easily with either hand. Okay, we have all heard enough. I only even mention most of it to demonstrate that I am generally pretty functional with both hands. A couple of months ago I started trying out some shavettes. I am telling you, I CANNOT do it with my off hand. I kept telling myself, "this is how you are supposed to do it", thinking that "Jesus, I should be a natural at this", all the while slashing myself to Hell. I don't know if it is an eye dominance, standing on your head in the mirror thing or what. I just can't do it. Switched to lefty only, and it was a piece cake. Not saying I am an instant master or anything, but lefty only, can get a SAS/DFS without donating any blood. Great post, curious to see what others say.
Another lefty here….and extremely-lefty dominant. EVERYTHING left-handed, especially actions requiring fine motor or detailed movements. I was sort of compelled to use my right hand for Straight razor shaving during the 4-5 months of pre/post CTS surgery on my left wrist. Slowly at first..VERY slowly, but with time, using my non-dominant began to feel more natural.
I'm not naturally ambidextrous, but since I was a teenager, I've made an effort to learn to use both hands equally well. It has helped tremendously with muscle fatigue on many occasions, from using a shovel or hammer, to welding and writing. Just take your time and try not to focus on the mirror at first. That will mess you up quicker than anything else.
I shave with a DE razor and use both hands. The right for the right side, and left for left side. You could use either hand but it may take some practice if you are not used to it.
I use both hands....just can't get the articulation of my wrist to do every stroke one handed. Takes practice and care but usually I tend to nick myself less with the non dominant hand than when using dominant hand on non dominant hand's part of the face. See geofatboy's videos. He's a two hander.
In March, I shaved using only my left hand (injury to right), and it was quite frustrating for a couple days, but became routine. It was an interesting exercise. IMHO, the human mind is amazing, and can learn anything when there are no other viable options.