Link betwen Austronesian and Salishan families

Question

In the Wikipedia article "Dené–Yeniseian languages", it mentions about

His [Vajda's] conclusion was that, contrary to prevailing belief, such structures are often preserved intact with little change over several thousands of years, and as a result may actually be stronger evidence of a genetic connection than the lexical relationships that are traditionally sought. As a result, he agreed with the consensus belief that lexical evidence of a genetic relationship becomes virtually undetectable after about 8,000 to 10,000 years of linguistic separation, but suggested that certain sorts of complex morphology may remain stable beyond this time period.

I've been noticing some similarities between Austronesian and Salishan language families, like: 1) Pervasive Reduplication, 2) Weak noun/verb distinction, 3) Alienable/Inalienable Possession, 4) Numeral Classifiers, 5) VSO word order, 6) Attributive markers, etc.

Could such theory that complex morphology and syntax, to a limited degree, are preserved intact be used to link these two families?

Answer 1

See my answer to a prior question about Vajda's hypothesis for a few potentially relevant remarks about Vajda's methodology.

If you want to use morphological or syntactic (or phonological) facts to establish a genetic relationship, pay attention to the following provisos:

1. The units of comparison need to be form-function pairings, not just forms or functions (1, 3, 4, and 6 are deficient on this count).
2. The form-meaning pairings have to be (typologically) unusual enough that you can plausibly argue that their coincidence is not due to chance (2 and 5 are deficient on this count).
3. You need to have a plausible non-linguistic historical scenario that matches the timeline you are proposing (this is probably the biggest problem with such a proposal).

Answer 2

The problem with taking this route is that it blurs genetic and typological classification. The attributes you list could be typologically correlated and have nothing to do with shared history, either through common descent or language contact.