Lol. Lets start off by saying i dont know you nor your skill level. Even if i did neither you nor i know the skill level of the guy currently bashing your face in, who you want to 1v1, so chances are you can fail. And when you fail, with how low the TTK is in general, that guy can turn around and cut me and maybe other allies down or decap a point while the rest of us thought you can handle it and stopped paying attention to that particular 1v1, and it would be our fault cause we let you sit there 1v1-ing the guy. Not to mention that even if you are wining the guy could just drop a "fuck you" grenade and either take out multiple people or even take down you fully, id rather have another ally to help attack/defend then a dead one cause i let him have his little duel. So yeah, each time i see a 1v1 im gonna fill the enemy full with shells from my bolt pistol, every single time. Because if you fail in your duel it could cost us the point/push, or in particular situations the whole game, id rather not think about that if i dont have to. Id rather nuke the guy and heal you up so you can go take more skulls then let you have your little moment while i uncomfortably keep your duel in the corner of my eye hoping you dont mess up. If you really want 1v1, pester the devs for a garrison-type mode where you can duel. Cause in a game with limited players in a match, where the actions of every player matter greatly, im not going to act in a way that is detrimental to the faction and the match itself. TLDR: No, shoot at everything!
leaving an enemy behind you clanging with another team mate while you move to the objective is dumb, means you have less ability to cap/defend because that person is preoccupied and there is no telling if the enemy combatant will simply beat him down and come after you.
Alternatively, if you're going for the cap/interrupt while they're fighting then the enemy combatant might just roll out of combat to stab you in the back before resuming said combat.
And if the enemy rolled through you your melee friend will hit you, stunning both of you and letting the enemy kill one, then refocus on whoever's alive.