I love playing a PLD, but most of their cross class abilities are fairly useless in a group setting.
Cure - useless unless you're soloing and want to exchange all your MP for HP.
Foresight - The only useful ability
Skull Sunder - absolutely pointless
Fracture - Not terrible, but you wouldn't use a gcd on this instead of one of your normal threat generating abilities.
Protect - Useless in a group setting
Bloodbath - useless with the amount of dmg pld can do
Raise - only helpful when out of combat/out in the open world to help others
Mercy Stroke - Not much point in using this unless you're soloing.
Stoneskin - This would be usefull if there wasn't always a healer that was already casting this on everyone.