Lux E doesn't double proc tear
tear normally procs with every spell cast. Some champs have abilities that you send out and recast and these count as two stacks for tear. Lissandra's E will stack when cast and stack when she teleports to her target location for example, or Janna's whirlwind Q will as well. Lux has a bug where he E will stack when cast but wont stack when it is popped.