Cleric Opinion on Fighter Spr

[Lacrima]

Everything I've read in the fighter forums is of divided opinion or in favor of personal choice as to whether a tank, and I stress tank here, should get 25 spirit for the 125 sp, 5% crit, and 75 mdef. Some say the extra sp is useful for skill spamming, others say the crit helps hold aggro. What I'm really curious about is how it affects a cleric who's healing the tank. Does the extra mdef help appreciably? I've read that some fighters just go full end and expect the clerics just to heal the massive damage they receive from magic attacks since they can just absorb them with their massive hp. Thanks in advance for responses. (Hopefully intelligent responses that is. -_-)