If only because it has a lower base, Divine Pact skills seem to be a little lower on average than Sorcery Grimoire skills. This means that sorcerors have a big advantage over Divine casters, in that a Spell Resistance makes the sorceror completely immune to the divine caster. For instance, last night the sorceror in my group covered the ship in Protective Wards of Spell Resistance (Hrestoli Liturgies grimoire 86%), and the NPC divine caster only had 45% in his Pact. Is there anything the divine caster could do, given that he didn't have Dismiss Magic? Well, there wasn't much he could do since he got taken out by a Befuddle on the first round, but in theory... I guess he could have just gone inside the ward.