The only time a WAR will need Goad is if you're doing a speed run - in which case, you might as well just put it on him/her once everything has been pulled and the OP spam is about to begin as it will have roughly the same effect as using it half way through their OP spamming.

Also Unchained + Berserk OP spamming is the highest damage you can do to all mobs per GCD. Usually all the mobs are dead by the time I've been pacified and I'm usually not bottomed out on TP at that point, however, I do run the risk of that if I go straight to the next boss and pull immediately. I had this problem in Snowcloak SRs and while it wasn't a huge issue it would've been nice to have a Goad in that situation.

Other than this very specific scenario where you're speed running a dungeon, a Goad macro is handy as the NIN can't see your TP and he shouldn't have to guess when someone will need it.