And I completely disagree with your point that evasion would negatively affect tanks more than DPS; that, to me, is preposterous. If a DPS build misses on one of its 2 button mashes, it severely decreases output. If a tank with a more balanced skillset (no dominant damage skills) misses, it does not.
Player A has 2 very high damage (2000) skills and 3 low damage (500) skills = 5,500dmg total
Player B has a balanced 5 skill set (1000dmg) = 5000dmg total
Player Hoever, ifA misses a 2000dmg skill, it lowers output to 3,500
Player B misses a 1000dmg skill, it lowers output to 4,000
Even if Player A misses a low damage skill and is @ 5,000
Player B is still @ 4,000 with a miss, but has 170% taunt from damage, so still has a higher aggro/DPS as far as the NPC is concerned.
Basically, mathematically, evasion as a matter of fact negatively impacts people with higher DPS and cost skills, because a miss means a much higher percentage of mods wasted (balanced builds don't stack mods as much), as well as endurance wasted (and they usually have longer cool-downs). So I don't understand your argument.