At the end of the movie Gattaca, well, I won’t explain the situation out of possibility of spoiling it. If you’ve seen the movie, you’ll know what I’m talking about.
The doctor says
This caught me somewhat by surprise; I am right handed, and I hold it with my left. Have all my life. I tried holding it with my right after the movie, and it didn’t turn out so well.
What’s the Straight Dope on this? Do most righties use their right? Or is it a mixed bag out of whatever you got used to as a child?
Unfortunately, this is one of Gattaca’s bigger plot holes. I don’t believe there is that strong of a correlation there. Oh well, still a good movie.
Rightie. I tend to use my right, though either hand will do, depending on the circumstances.
To all I may shake hands with: I wash thoroughly. Don’t look at me like that.
I’m right handed, use my right hand, and sometimes forget to wash thoroughly.
But probably not right before I shake hands with you.
I can’t speak to the truth of that statement, however, there are various reasons why, if it is usual for right-handers to do that, you use your left.
You might have been taught to use your left hand. In various cultures, the right hand is used for “clean” things and the left for “unclean” things. Even if your family has no clear assumptions about this, it might have been the way boys in the family have been taught for generations.
Your “handedness” may have been switched. Many children are encouraged to use their right hands for daily tasks (i.e., handwriting) but still retain the left hand familiarity for tasks where handedness isn’t normally noticed.
I’m right-handed and my mom says I wasn’t switched, but, according to her, I do many things left-handedly (backwards). So, it may just be a matter of brain preference 
I really wouldn’t worry about it too much - who cares what hand you hold it with?
My extensive research on the topic leads me to believe those right-handed who use their left may suffer from “left-hand envy”, and those left-handed who use their right are more likely to be simply confused.
Right handed here and can’t imagine using my left. I’m sure there would be significant clean-up if I were to try. I just watched Gattaca, coincidentally, and I bought that line completely, just because it made sense to me.
Jammer
It’s the way the fly on trousers is made. Unzip with right hand and extract with left.
Aside from habit you will find it akward to unzip with left and and extract with righe.
In a society where there is only one norm, lefties are abberant, thus everyone should be righted-handed anyway.
I never got in the habit of just unzipping the fly before springing the snake from its cage. I’ve tried that method, and it always felt uncomfortable; and worse, seemed to increase my chance of embarassing “spottage”.
Ah, but what about the patented 3 step method?
Personally, I never touch the sucker less I’m looking for a little loving. I usually just pull down my pants and little Herbie perks up!!
I feel that the intent of the line was to emphasize that
the doctor knew that Vincent/Jerome was an In-Valid from the moment he had his “job interview.” It just lends an extra kick to the revelation that the doctor has him figured out. Not only does he know what Vincent/Jerome is, he has been, in his own way, aiding and abetting him from the beginning of his fasttrack career. It adds a message of hope to the otherwise dismal distopian setting – that resistance to the eugenically-correct world is more widespread than it seems.
Whether or not the line is true is pretty much a throwaway.