Understandable, but at the same time you're limiting certain playstlyes. What I find to happen most of time is that the winner is the player that runs up to the other opponent from behind, really that's the how you win. You get more opportunities than the other person. Not really skill, just luck.
For instance in MW3 my friend invited me to try out for a clan that he was in. I didn't have a very CoD based friend's list at the time so I decided to go ahead and try. We had a 1v1, 3v3, and then a 2 public matches. In the 1v1 I got stomped. The kid that beat me just kept getting lucky and finding me with my back turned. I'm a pretty smart player, I check my corners and set myself up for the best possible outcome, but I just couldn't get seem to get any oppotunities like he did.
The next 3 matches we played though I finished near the top of the lobby and that's what got me in the clan. In fact it wasn't long that I made my way onto their A team, probably less than a month of playing.
Fact is, 1v1 isn't really a test of skill. However, if you find it fun then by all means go for it. There are a lot of players who do enjoy playing. I'm only posting all this for the sake of debate. This isn't in mean spirit at all.