"Wise and learned in the scrolls of lore and song, and yet a man of hardihood and swift judgement in the field. Less reckless and eager than Boromir, but no less resolute."
I have found 2 different approaches of nasal mutation in 2 different places (one of which being Thorsten Renk Sindarin course, the other one very structured course inspired also by this site):
1. nasal mutation changes "d" into "n", but "dr" stays the same (Thorsten).
2. nasal mutation changes "d" into "n".
so, two "wolf" plurals emerge:
"in droeg" and "i nroeg" (for this latter "n" is suppressed)
why am i tempted to "feel" the second one is the good one?
Why are you tempted to "feel" that i nroeg is the good one? I think it's because in i nroeg mutation seems to occur, while in in droeg there's obviously no mutation.
If you look at CoE's sindarin mutations chart you'll see: DR → IN DR (no mutation nor assimilation – thus, droeg → in droeg), just like in Thorsten Renk's sindarin course. Personally, I would go with in droeg, but maybe i nroeg can also be correct, if neither DR → IN DR or DR → I NR are attested (regarding nasal mutation, this is the case with L → I L vs. L → IN L).
[Edited on 04/14/2015 by Varyalener]
Lindanen lassis, laurië lassis. Ar tás altaner laurië lassi.