It is confusing
If one were to collect all references to some sort of 'Last Battle' or World End tale or belief it would make for quite the post I would think. Anyway, what I'm trying to suggest above (at least) is that
if the 'content' of the Second Prophecy (meaning only the 'latest' version on paper that we have) were cast as Mannish in origin (as seemingly according to note 7) then it is perhaps no longer
The Second Prophecy of Mandos in that it is no longer
another prophecy
from Mandos specifically. Or, if 'put into the mouth of one of the Powers', put there by Men (raising the question of its true origin as a saying).
That's just one possible way of looking at it (I think), especially if one emphasizes note 7, which in my opinion could 'fit' well enough with the conclusion of the Valaquenta (which CJRT used to conclude the Quenta Silmarillion proper instead of the Second Prophecy). The late note on Turin coming back at the end of the Elder Days doesn't necessarily 'fit' with the Second Prophecy -- but one thing I note about it (despite how one interprets its meaning with respect to the question as a whole) is that it is not a foretelling of Mandos (one of the Powers) in any case.
If we narrow the consideration (arbitrary yes) we have:
A) the conclusion to the Valaquenta: Mandos does
not declare something about the marring of Arda being amended.
B) Note 7: the Prophecy is Mannish not from Mandos (or arguably distancing him even if 'Men say' the Vala himself delivered the prophecy)
C) The prophecy of Turin is given by a mortal women (not Mandos).
So this could be said to be a 'common element' despite what C may or may not say about the issue as a whole. The late prophecy (C), if indeed Christopher is correct, refers to the War of Wrath rather...
... but what it means just by existing as a text (considering Turin's 'earlier' role in the Second Prophecy) is another question. And there are considerations of other references to World End battles or World End traditions (including when each was written) that get tossed into the larger mix of course. I'm not going into that complicated business, but am rather trying to note a possible 'general trend'
away from Mandos if any 'prophecy' is going to be given.
That is, at least with respect to
some texts anyway, so the force of this is diminished -- as I can't really say, for example, that the cursory corrections to the end of the QS proper are necessarily 'removed from Mandos' especially considering the further subheading
The Second Prophecy of Mandos.
Oh well
