There are far too many spells on the loot table for the various classes and too slow a drop rate.
We spent weeks in Skyfire killing hundreds of mobs and many of the mobs listed for this spell. I came away with 3 bags of spells for all that trouble and no Forlorn Deeds.
We were able to get all four pearlescent shards for the cleric but no sign of this spell.
Forlorn Deeds drops rarer than epic drops?! Been searching the bazaar for the last 3 weeks and not once has this spell been available on FV.
We've leveled beyond it just searching for it and now will wait for the 65 spell Dreary Deeds (banked).
When the drop rates are so slow as to be inane, there's no point in earning it.