I'll use Experiment 18-A as the example since it's what I'm looking at. It says it does 30 points of Kinetic damage(?) and 30 points of Energy damage. Assuming no damage mitigation is applied, does that mean it does a total of 60 damage or is it an either/or situation that depends upon the target's resistances?

The reason I ask is because I'm trying to compare the total damage output to a weapon that deals only a single damage type.

It's 60 total damage hypothetically. Of course nothing in the game actually has 0 defense so in practice it's 30 reduced by ballistic defense + 30 reduced by energy defense