If you don't want to allow extrapolation, don't insert what isn't there, either. If costs for all other durations are listed, the absence of one should interpret that it is not available.
Making it obscene is to prevent Uber-builds from crafting weapons with True Strike; otherwise everybody is a glass canon and fights are resolved by who wins initiative.
Aboyd listed some very good ways to achieve multi-dice damage effects for a weapon. But at the cost, the party is of a level facing things with resistances to help balance the increased damage output. And the multiple energy attacks are more likely to have some effect; the Weapon/ Jack-of-all-trades, something is going to get through. The ISW weapon would give no bonus damage vs constructs, undead, et al.
In general I'm more of the mind to not allow instantaneous effects on a continuous basis.
The 'comparative damage' allows a guideline for the effect, sidestepping the difficulties of the process. If it stops there, fine. But if used to gauge the cost of similar effects...
Substitute the Inflict Serious Wounds for a nice Vampiric Touch... Two very similar spells; level (spell & caster), duration, effect, and damage (5d6 vs 3d8+7 is pretty close). But healing the wielder on EACH hit; Nightmares for DM's with monks and multi-attack melee apes in a party.
Making it obscene is to prevent Uber-builds from crafting weapons with True Strike; otherwise everybody is a glass canon and fights are resolved by who wins initiative.
Aboyd listed some very good ways to achieve multi-dice damage effects for a weapon. But at the cost, the party is of a level facing things with resistances to help balance the increased damage output. And the multiple energy attacks are more likely to have some effect; the Weapon/ Jack-of-all-trades, something is going to get through. The ISW weapon would give no bonus damage vs constructs, undead, et al.
In general I'm more of the mind to not allow instantaneous effects on a continuous basis.
The 'comparative damage' allows a guideline for the effect, sidestepping the difficulties of the process. If it stops there, fine. But if used to gauge the cost of similar effects...
Substitute the Inflict Serious Wounds for a nice Vampiric Touch... Two very similar spells; level (spell & caster), duration, effect, and damage (5d6 vs 3d8+7 is pretty close). But healing the wielder on EACH hit; Nightmares for DM's with monks and multi-attack melee apes in a party.