It's over, Snape is evil /Ruthless Dumbledore?

[zgirnius]

No: HPFGUIDX 138493

Alla wrote:

> Nope, I think that he needed Snape to heal him.
> 
> Just me of course,
> 
> Alla.

zgirnius:
I did not address this in my post, but I have an opinion which was 
implicit in the scenario I described. (I suspect this opinion in some 
form was expressed in Severely Sigune's excellent Snape post...)

As I see it, the potion in the cave is something Dark and dangerous 
like the curse of the ring, not just a (relatively) simple matter of 
making an antidote. So I agree, DD was expecting Snape to heal him, 
with his expertise in both DA/DADA and Potions. Only, if Snape is 
dead from breaking the UV or fallen in battle with several DEs, he is 
no longer available. If like the ring curse it requires relatively 
quick action to counter, death for DD seems a likely outcome.

Of course, you are right that we do not know how dangerous the potion 
and its effects were, how timely an intervention was required to save 
DD, or how widespread the knowledge to heal the damage is. I feel 
that at this point the data we have are insufficient to give a 
complete explanation of all the actions and observed facts presented, 
so we all need to make some reasonable-seeming assumptions to come up 
with coherent theries. To me, the idea that the potion is of 
sufficient lethality to require very timely intervention, by Snape, 
seems reasonable given we are told by DD himself that such was 
necessary in the case of the Ring Horcrux. 

If it turns out to be some Potion Sluggie could whip up an antidote 
for in no time, I will not have difficulty accepting that Snape 
killed DD solely to save himself. (Or even, if other ambiguities are 
clarified in ways that support such a theory to my mind, that Snape 
killed DD out of loyalty to LV/the DEs.)

I would not imagine that DD would want Snape to kill him merely to 
get Snape closer to LV, that does seem a bit much. But I can 
definitely see the events of the Cave and the Tower putting DD in a 
corner where that starts to seem the best way out of a disastrous 
situation. I am not in the DD told Snape to kill him before Snape 
ever took the UV camp...More likely, I would guess that Snape saw the 
options available and the likely consequences, and had concluded the 
best option (in the sabe that is saves the most lives/souls and 
removes a considerable danger for Hogwarts quickly) would be to kill 
DD and clear out with the DEs, and DD legilimensed this in the 
moments they gazed at each other after DD said "Severus". Then the 
follow up "Severus, please" would have been to confirm to Snape that 
DD agreed with this analysis of the situation.