Can you benefit from the Dueling fighting style after having thrown a light weapon?

Question

So, the PHB has this to say about unsheathing a weapon (page 190)

You can also interact with one object or feature of the environment for free, during either your move or your action. For example [...] you could draw your weapon as part of the same action you use to attack.

So, if I had already a short-sword in one hand, I could technically draw the dagger dangling at my belt and throwing it as part as the same action, correct?

And since they're both light weapons, I could then use my bonus action to attack with my short-sword (without the proficiency bonus on the attack roll), right?

But would that attack benefit from the +2 damage bonus from the Dueling fighting-style, since I did attack with only one weapon in hand, or wouldn't it count since I technically used another weapon during this turn?

Answer 1

The Dueling Fighting Style does not care about anything you have previously done on your turn; only whether you have one weapon in your hand when you attack with it

The Dueling Fighting Style states:

When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.

It gives you a bonus to damage rolls if you are wielding one weapon, and it is a melee weapon in one hand. It does not care about anything you have done previously on your turn.

Thus, when you take the Attack action while wielding two weapons (which is required for Two-Weapon Fighting to work) you throw one weapon at first. Now you have one weapon in one hand and no weapons in the other hand which lets you qualify for the Dueling Fighting Style's damage bonus on attacks using this second weapon.

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You've also slightly misunderstood how Two-Weapon Fighting works (or perhaps made a typo of sorts). You said that you don't add your proficiency bonus to the attack roll but this is not the case; what the rule actually says is this:

[...] You don't add your ability modifier to the damage of the bonus attack, unless that modifier is negative. [...]

You do add your proficiency bonus to the attack roll, as you are attacking with a weapon your are proficient with; however, you do not add your ability modifier to the damage roll (unless you have the Two-Weapon Fighting Fighting Style)