I don't know how to put this tactfully, so I'll just say it ― as I see it, the 3S Committee is going in the wrong direction. It is committing what Jacques Barzun calls the preposterism fallacy ― putting the end at the beginning. The following is from my "Notes and Quotes" web page on Education, and is from Barzun's Begin Here.

[In an essay titled 'The Urge to Be Pre-Posterous,' Barzun expands on the concept of preposterism, which he explains elsewhere. Preposterism is, as Barzun puts it, putting "the cart before the horse." (83) Preposterism is, in effect, an educational reform which puts the end at the beginning. It attempts to teach the child, beginning in kindergaten, EVERYTHING that an adult knows about a subject. The following comments are primarily about new math, but they touch on linguistics and the teaching of grammar. I have quoted at some length because what he says is very relevant to many attempts to reform the teaching of grammar.]

"From seeing that the teaching of arithmetic could be made more interesting and challenging by a dose of imagination and reasoning, the makers of the new program concluded  that teaching calculation was trivial and must be replaced by 'conceptual work.' They taught 'Commutativity' and 'Associativity' as part of addition and multiplication and went on to prescribe difficult feats of a kind that belongs to pure mathematics, has no daily utility, and my even undermine it. . . . .
     This demand was only one among others of the same kind: number theory, sets, relations, probability, and other delightful aspects of numeration were drawn on to flex the muscles of beginners. The group planning new math at MIT was having a good time, because these large subjects naturally interest them, whereas multiplying fractions and extracting square roots are dull and can be left to hand calculators. How to cut up the new complexities for child consumption was the attractive task. It was as good as a game. If the game succeeded, it would be a great leap in school performance, visibly due to the intervention of high professionals in the lower-school curriculum.
      That feeling was natural enough; it is the flow of ostentation that Quintilian noted a while ago. But there are other motives behind the modern desire to 'begin where the teaching should end.' One is the fear of being incomplete and inaccurate -- too far behind [84] the point that 'the profession' has reached. In short, it springs from a misplaced regard for scholarship.
     How else explain some of the grammars handed to youngsters of 12 to 16? They are books of four to five hundred pages, filled with terms special to themselves and illlustrated with quasi algebraic formulas. They propound in practice one of the competing doctrines of modern linguistics--structuralist, transformatiionist or other. 
They shun the use of such words as noun, object, preposition, which might enable the students to understand what most people continue to say when dealing with sentences. For those words are 'inexact' and 'unscientific.' The advance of linguistic theory after Henry Sweet, Saussure, and Jespersen has made them obsolete.
      With this attitude goes the abandonment of two related ideas that up to now have never been absent from the theory of education. One is the notion of rudiments. . . . .  'Rudiments' comes from the root for 'tear apart.' They are the portions of a subject torn apart from the rest to serve as points of entry into the field. . . . Thus the letters of the alphabet are torn from the word and sounded to show the child how to read and spell. Likewise, the so-called parts of speech are convenient groupings to display the elements of a sentence.
      What bothers the superstitious modern mind is that these and other rudiments falsify -- and they are not the whole story. Just think: using the alphabet by itself in phonics is a fraud; the same letters do not always mean the same sound; and the parts of speech similarly overlap and fail to explain everything that goes on in human discourse. Poor children, who from the word go (literally) are misled! The fact that phonics teaches them how to read and old-fashioned grammar helps them to write acceptably seems a crude kind of success compared to the righteousness of total disclosure of what's what from the start -- as if there would never be another chance to modify and expand knowledge later on. It is this compulsive scientism that makes for the nationwide failure to teach the so-called basics -- the all-important rudiments -- from the kindergarten onward." (84-85)

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Forgive the long quotation, but it aptly describes what I see in the 3S discussions thus far ― the attempt to be "scientific" and all-inclusive, and the attempt to drag bunches of linguistic concepts into a basic pedagogical grammar. Martha, for example, writes:

"I feel certain, Ed, that all of us--not just you--will have to compromise on many decisions.  I envision a document that includes alternative interpretations in many places and cases.  But I feel very strongly that we have to find ways other than the traditional eight-parts-of-speech way to describe language.

"[Note:  One of those cases may be the sequence I FEEL STRONGLY!  How else to interpret that other than as an exception to the NP linking-V Adj pattern?]"

It seems to me that Martha here needs to deal with an "exception" because she wants to include linking verbs (and why "feel" has to be a linking verb here is itself debateable). Eliminate "linking verbs," and students are faced with a simple subject and verb, with the verb modified by an adverb.
         As another example of preposterism, Johanna wants morphology to be included in the discussion of language development.  I, for one, have absolutely no idea of why it should be.  In essence, it seems to me that the committee is creating a sledgehammer which English teachers will have no desire to lift. 
Ed