If you're the sort of person who abuses obvious RAW loopholes, the Lucky Paladin dual wielder could drop prone or close their eyes before attacking to induce disadvantage-for-super-advantage...
Pretty sure... I think either you roll 1d4+1 three times, and therefore add +2 to each one, or you roll 1d4+1 once, add +2 to that, and that's the damage of each dart.