1. a 10 minutes 1v1 fight? really dude?? i dont think thats possible even if both players are rocking full sta/tough gear and surv traits.
2. exotic is just a minor upgrade from rare (except weapon). the good thing about GW2 is because its not all about gear.
3. mesmer is a very good solo\small group pvp class.
4. if you are getting stomped in duels by a mesmer over and over, you are getting outplayed, simple as that.
Finally, the issue while playing a smart mesmer is that he will use\abuse his clones to waste your cds and avoid dmg. But since you are playing WvW since beta, you should be used to it by now.