GCD gap closers are quite good because they present interesting uptime options: you can break tethers in P4-2 and return to the boss with these, for example, avoiding the use of a weak ranged attack like Throwing Dagger or Tomahawk in the case of WAR and Primal Rend.

They are an extra uptime tool available for NIN so imho there's no reason to remove it, even if it's more situational.