A weapon with Treasure Hunter that increases your blueprint drop chance by 10% does exactly that. If a blueprint has a 10% appearance chance it will now appear 11% of the time.
There is a bug where the tooltip on the rewards screen shows the wrong number. It should display the sum of all players with the Treasure Hunter perk
Interesting-- so the % shown on the rewards screen is just for that one, specific, weapon? And if there's 3 weapons on one map, it might be 5% (rare) 10%, 10%? But then it would feel like that is only giving us a much lower total than shown on the forge screen, still.
What you said makes sense, but it also makes the forge number seem misleading. Is there any chance we could get an in-depth look or explanation about the forge system, drop rates, etc.?
video or even just a written guide. I would like to maximize my drop potential, but if it is just giving a total of 1% per weapon, it feels like a waste of points that could go into making a stronger weapon to have an easier time playing.