[PnP] Rule 4.511 Spell Failure due to injury

[Alex Koponen]

Rule 4.51 "...The spell cast will not go into effect until all points 
cast for it have been allocated. When they have, it takes effect in the 
Magic Effect phase immediately following."
Rule 4.511 states "If a magic-user is damaged while casting a spell, 
i.e. before all mana has been allocated to it, the spell will not take 
effect and any mana cast is lost. He must start over to cast the spell."

Combined with the  phase sequence of Mana Allocation/Missile Fire/Magic 
Effect/Move & Melee this presents some questions of interpretation.

Presuming a magic-user is fast enough to fully cast a spell in one phase 
(casting speed > or = to casting cost) will the spell take effect 
regardless of how much damage the mage took during the missile phase? 
[Since the mana was fully allocated before the missile phase.]

Some GMs rule that the mana isn't fully allocated till the spell takes 
effect. Thus ruling that a missile can interrupt a single phase spell.

Option:
Perhaps damage suffered by a magic-user should reduce the likelihood of 
the spell's success and increase the chance of spell failure and abysmal 
failure rather than automatically negating the spell. Say 10% modifier 
for each point of damage?

One could get more complex and say % of HPV or add in a Will roll to 
reduce (perhaps to half) the penalty.