there are a little bug from any skills what are generating a LOL agro,for example: http://www.wowhead.com/spell=586 IF you have boss agro,and you use this,are working,but when effect is finished,when debuff expires,you win all agro,for example:
tank are tanking a boss and boss Summon a add,you have Agro 0 with boss,and you attack to add,andyouuse this,when effect is finalized,you have agro 100% from boss, and add,if you're un world and are 6 people fighting withmobs,and you're fighting with a mob,you win all agro from all players fighting in a zone if you use http://es.wowhead.com/spell=58984 the same,you win agro from battles what you're not involved
P.D too are skills what doesen't generate agro,but they generate a gran cuantity of agro,for example spell=48078 or any talents for example this talent 33202