The Shibboleth of Fëanor

[Galin]

I agree the reference is to Fëanor and Galadriel. And to ramble...

The term Eldar is a bit tricky, but includes the Sindar in any case. Tolkien appears to have published that the term Eldar does not include the 'East-elves' of Mirkwood and Lórien, and I find Christopher Tolkien's entry in The Children of Húrin interesting here: 'Eldar The Elves of the Great Journey out of the East to Beleriand' -- especially in comparison to the more well known entry in the Silmarillion index, which could include the Silvan Elves of the Anduin Vale, for example.

The Lord of the Rings also appears to say that the languages of the East-elves (of Mirkwood and Lórien) are not considered Eldarin. The Tawarwaith of the Anduin Vale could be Eldar according to Quendi And Eldar, where it is said that Elda remained the chief word for 'Elf' but was not in accurate use held to include the Avari, taking on the sense of Eldo, a 'Marcher'. And the Silvan Elves of Mirkwood and Lórien are considered Eldar according to late notes on the Tawarwaith (or at least were Eldar 'in origin').

Perhaps the word narrowed in application:

A) originally all Elves are Eldar 'Star-folk'

B) but then Eldar properly denotes those Star-folk who are Marchers -- as opposed to those who are Avari, or refusers.

C) and then, Eldar refers to the Star-folk/Marchers who made it into the West, which includes Beleriand (noting: save the Sindar only, in Appendix F). In other words, the word narrows again in application, and the Eldar are the 'West-elves'.

In any case C is what Tolkien himself published (as I read things), and IMO even he would need to deal with this description.

[solicitr]

In any case C is what Tolkien himself published (as I read things), and IMO even he would need to deal with this description.

Problem is Tolkien kept changing his mind, and it's not easy to discern what his "settled" thinking (if any) was on some matters. In the late 30's the Danians of Ossiriand were Pereldar "half-Eldar." In the 50's rework which wound up in the published Silmarillion the Nandor on both sides of the Mountains appear to have been promoted to full Eldar, with (I believe) a language derived from Common Eldarin. Certainly the tiny Silvan vocabulary T provides appears to be little more than a dialect of Sindarin (e.g. "Legolas means "green leaves", a woodland/Silvan name. It is a dialectical form of the pure Sindarin laegolas.").

Of course, T couldn't even decide whether Silvan was spoken at the end of the Third Age or not!

Underlying all this, I think, was a desire to establish that the populations of Mirkwood and Lórien "counted," so to speak.

[Galin]

True enough. I tend to question the true measure of intent behind private writings if they are arguably problematic with material already in print -- especially if there is no real evidence that JRRT remembered something already published, and thus was fully considering a given matter.

You already touched on the matter, and IIRC Tolkien did not reveal much of the Silvan tongue in anything he published, and I think that even Legolas isn't necessarily a woodland compound (although a woodland name in meaning), but a Silvan pronunciation of Sindarin Laegolas -- in other words, made up of Sindarin but -ae- pronounced as -e- here when the Silvan Elves spoke it. Appendix F notes that in Lórien Sindarin was spoken, though with an accent, and that certain names are probably of Silvan origin, adapted to Sindarin, so I think the published Elvish in this realm (small as you note) is accounted for.

However, it remains that in The Lord of the Rings, the general implication is that these Silvan Elves can pass Over Sea, in any case.

[solicitr]

What T did publish suggests that his "final" (hah!) thought on the matter was that Silvan/Nandorin had ceased to be a spoken language by the end of the Third Age.

But what then to make of Legolas' "It [the Lay of Nimrodel] is a fair song in our woodland tongue"?

It may be possible to liken the "woodland tongue" of the LR period to the "Scots" of Robert Burns: a dialect of English with a pronunciation and vocabulary influenced by the Gaelic of its speakers' ancestors, and potentially unintelligible to users of "standard English."

[Galin]

Ahh, good notice of Legolas' line there!

Perhaps this alone could have influenced his 'final' thought?

Though the example you note seems possible anyway.

[Infidel]

These two kinsfolk, the greatest of the Eldar of Valinor,(14) were unfriends for ever.

Who together with the greatest of all the Eldar, Lúthien Tinúviel, daughter of Elu Thingol, are the chief matter of the legends and histories of the Elves

As I said, I have always read it the as 'the Eldar of Valinor (of which F & G are members) and Lúthien are the chief matter of the legends...'.
I think I have interpreted it in that manner because Galadriel is not essential to the history (as written), at least in the First Age nor consequential enough for me to consider as a chief matter (at least not until later ages).

[solicitr]

It may explicate Legolas' line a bit to recall that at the time Tolkien wrote the chapter, he envisioned the Common Speech as being of Elvish origin, based (one would suppose) on Ilkorin of Doriath, which was quite distinct from "Noldorin" (the future Sindarin).

The idea of the Mannish Westron came around much, much later.