Wrathamon
Adventurer
From the way it is worded...
A +1 bow of Goblinbane shooting +5 arrows would be effectively shooting +5 arrows of Goblinbane, so +7 vs Goblins.
Where the +5 Bow shooting +1 arrows of goblinbane would only be doing +5 as the goblin bane doesnt jump back to the bow, as it is worded so they would be +3 arrows but the bow is +5 so you would use the higher of the two enchantments.
So this is a case where higher + enchantments on arrows is a better situation than having it on the bow and a reason to carry around magical arrows.
A +1 bow of Goblinbane shooting +5 arrows would be effectively shooting +5 arrows of Goblinbane, so +7 vs Goblins.
Where the +5 Bow shooting +1 arrows of goblinbane would only be doing +5 as the goblin bane doesnt jump back to the bow, as it is worded so they would be +3 arrows but the bow is +5 so you would use the higher of the two enchantments.
So this is a case where higher + enchantments on arrows is a better situation than having it on the bow and a reason to carry around magical arrows.