First of all, i would say that the job for a thief isn’t to 1v1. His job in PvP is to help his teamates and change a n v n situation into a n+1 v n situation.
Let me me explain this more: Thief can’t actually duel any other class.
A very skillfull thief can’t duel any other skillfull class because the gap is too big. You’ll counter by saying: “u can dodge, u can get stealthed, u can rupt, u can time” and i’ll agree, but the only way to win against anyone in duel is to make zero mistake while your opponent makes many.
A good Warrior/Mesmer/Inge/Ranger/Guard/Ele will wait until you’ve used all your breakstuns/dodges to burst/CC you and kill you.
A good Necro/Guard burn/Inge condi will wait a good opportunity and put all the condi he can and just kill you.
Of cours, I’m talking about good players, you can easily find trashy people and 100-0 them. but on the competitive stages, thief is the lowest class actually.