Some reasons I can give for this 1 . Leech as a form of defense is iffy . Sure , you can leech retarded amounts if you get hit by a large hit , but that doesn ' t save you from one shots , which I presume blade flurry characters might be more prone to due to the nature of the skill , which requires you to stay in a spot to deal damage . This is further exacerbated by the fact that a berserker takes 10 % more damage from the passive . This is not to say that being an assassin allows you circumvent those issues , but leech is not a clear cut advantage for berserker over assassin . 2 . Superior start location is more impactful than what you give it credit for . The assassin start is closer to the swordclawdagger nodes that one might want to pick up when going a crit bf character , adder ' s touch and night stalker being some of the more prominent notables . Whereas the marauder start has only the disemboweling cluster , which is awesome in its own rights . The start location of shadow with cluster that you want to pick up in close proximity to the starting point allows for lesser travel nodes , which could be used to pick up points in other areas . i . e . crit crit multilife etc . I ' m not too sure how accurate your statement that 40 % more damage is equivalent actually slightly better than all the chaos 100 % more poison damage assassin gets as I have yet to run the numbers myself but I ' m leaning to no . You ' re forgetting the other effects of the nodes which include main and reduced DOT damage taken , as well as the amp damage on the berserker node which gives 40 % more damage . All in all I do believe that it ' s a matter of preference , and if you feel like you would like going berserker for the leechdamage and would like to discount what assassin brings to the table which might see changes anyway given possible poison changes coming up ? , you ' re free to go for it . That ' s the beauty of PoE