This line doesn't make any sense. The Q-35 cannot deal less than 68 damage on a critical hit, because critical hit damage is not affected by DT (62), and DT cannot block more than 80% of a single strike's damage (which in the case of the Q-35 would put it at 6.4, not sure whether it rounds down in that case).
Edit - That is my understanding of how critical damage is applied, anyway.
If I remember correctly critical hits are mitigated by DT if weapon damage alone wasnt enough to penetrate targets DT. Examples:
DT of enemy: 30
Better Criticals (critical hit damage bonus x1.5)
Sneak attack crit (2x damage)
Overcharged ammo (+25% damage)
Lord Death rank 3 (+4% damage)
Plasma Caster:
Base damage: 65
Crit hit damage bonus: 65
(65 + 65 x 1.5 - 30) x 1.25 x 1.04 x 2 = 344.5 damage
The DT is only subracted once per attack so because plasma casters base damage of 65 manages to penetrate enemys DT you could say that critical hit damage bonus ignored DT.
Gatling laser with weapon mod giving + 3 damage:
Base damage: 7 + 3 from mod = 10
Crit hit damage bonus: 7
(10 + 7 x 1.5 -30) x 1.25 x 1.04 x 2 = 10.66
The reason why I got 10.66 (if im using the correct formula) is found within the brackets.
10 + 7 x 1.5 = 20.5 is lower than the targets DT of 30 which mean that the damage dealt wasnt enough to pierce through the DT. In this situation the game will let 20% of the damage done before DT is factored in through which is 20.5 x 0.2 = 4.1 and use that value for the rest of the damage calculation as follows:
4.1 x 1.25 x 1.04 x 2 = 10.66
In this example not even the added crit damage was enough to pierce through the targets DT and therefor the game only let 20% of the damage through before % modifications.
Plasma Pistol:
Base Damage: 22
Crit damage bonus: 22
(22 + 22 x 1.5 - 30) x 1.25 x 1.04 x 2 = 65
Here the added critical hit damage bonus was enough to sort of push the base damage to overcome the targets DT and SOME of the critical hit bonus was used up for that so to speak. As clarification:
Normal ammo
No perks
Normal crit
(22 + 22 - 30) = 14
Normal hit
(22 - 30) = 4.4 because damage not enough to penetrate DT -> 20% of 22 used = 4.4
Here we see that doing a critical hit didnt increase the damage by 22 because some of that added damage was used to overcome the targets DT -> damage done with crit 14 instead of 26.4
I know that the formulas and whatnot are used a bit incorrectly because I couldnt think of a way to incorporate all the damage vs DT checks and what the game does in which situations into the formulas.
Again, Im not 100% if these formulas are correct as I got them from these forums some days ago and havent done that much ingame testing on them.