Now that people are discussing it, 5% protection does not seem like very much. Think about it--if you want one buff to be good for one hit, that would mean it takes 20 hits normally to strip protection off. For example, if you had 30,000 max protection, 5% would be 1500. At levels where 30,000 protection is competitive, 1500 is much less than a non-crit hit. So you would need multiple frequent buffs just to gain enough for one extra hit. Chirrut and zeta k2 with Leia would seem like a must. Could work on pathfinder with Chirrut too (who you'd wnt anyway because of the aoe expose). But compared to 20% health recovery on a crit for Barriss, it seems like not very much for a zeta.