I think you're on to something Rebecca.  Good sleuthing!  I note, too,
that the "as" clauses can all be placed before the main clause -- except
for1b, which sounds even more unnatural in that position than it does
following the main clause.

On Fri, 27 Aug 1999, rebecca s. wheeler wrote:

> Hi folks,
>
> Regarding the example 1b which sounds bad...,
> >
> > > 1-a. You carried the luggage yourself, which was not necessary.
> > > 1-b. You carried the luggage yourself, as was not necessary.
> > > 2-a. He is a foreigner, which is evident from his accent.
> > > 2-b. He is a foreigner, as is evident from his accent.
> > > 3-a. Her feet were bare, which was the custom in those days.
> > > 3-b. Her feet were bare, as was the custom in those days.
> > > 4-a. She has married again, which was natural.
> > > 4-b. She has married again, as was natural.
> > > 5-a. Tom was not at home, which is often the case with him.
> > > 5-b. Tom was not at home, as is often the case with him.
>
>
>
> I note a difference between example 1, and the others which may be relevant.
>
> Note that the first which/as clauses have "not" inside them. None of
> the others do. Indeed, if we take out the "not", 1b becomes just fine:
>
> 1b: You carried the luggage yourself, as was necessary.
>
> I THINK that's fine.
>
> So, something is going on with the "not" element. Question is what.
>
> Notice,
>
> 2a. He is a foreigner, which is not evident from his accent.
> 2b. He is a foreigner, as is not evident from his accent.
>
> While 2a may sound a nudge odd, 2b is flat out bad, I think. What I
> SUSPECT is happening is that "as" functions to join clauses which are
> alike in meaning in some significant way. That is, like "and", "as"
> signals commonality or affirmation. But when you bring in a "not", it
> seems that there is a clash with "as".
>
> Notice,
> 2c. He is happy, as we can all see.
> 2d. He is happy, as we can not all see.
>
> The contrast of final clause with first clause becomes fine if we put
> an explicit contrast word in.
>
> 2e. He is a foreigner, although it's not evident from his accent.
>
> There's surely more to the story, as seen in 2f. Here, there is no
> explicit connecting word (e.g. which, although, as), and the "not" is
> perfectly good.
>
> 2f. He is a foreigner, a fact not evident from his accent.
>
> So, I think that the problem has arisen in the original sentence 1b
> because "as" signals a "continuation" in some sense of the meaning of
> the first clause, but then the "not" signals a clash.
>
> so, whatch'all think?
>
> cheers!
>
> rebecca
>
>
>
>
>
>
>
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
> Rebecca S. Wheeler, Ph.D.
> Assistant Professor of English
> Department of English                   phone:  (757) 594-8891
> 50 Shoe Lane                            fax:    (757) 594-8870
> Christopher Newport University          email:  [log in to unmask]
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>
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>