Daniel -
Your reference to the genetic testing makes less sense the more I think about it, if you were talking only about the polyandrous unions. Genetic testing has yet to identify an offspring of Joseph Smith from any of his plural wives, including the ones with only him as a husband. Yet you seem to agree it's a given Joseph Smith had sex with them. So I'm entirely confused as to your point with the testing.
This is what you seem to be saying (and I'm not trying to put words in your mouth but rather restate my understanding of what you are saying so you can see where clarification is needed)
1. Joseph Smith had sex with his nonpolyandrous wives.
a - genetic testing has not yet identified offspring from those wives
2. Joseph Smith may not have had sex with his polyandrous wives and the fact that genetic testing has not yet identified offspring from polyandrous wives supports that contention.
You see my confusion? Just what does the testing prove or not prove to you?
(by the way, does anyone know which wives' testing has not yet been concluded? Isn't one of the "jury's still out" wives polyandrous? - Mary Rollins Lightner? Or have I misremembered? anyone have a link to information about the testing?)
Never mind, I answered my own question, yes, it is a polyandrous wife still being tested: (but not lightner's since that son died as an infant, I just misremembered which polyandrous wife)
http://www.wivesofjosephsmith.org/DNA.htm
Ongoing research includes evaluation of Josephine Lyon (Sylvia Sessions Lyon) autosomal DNA. "Hundreds of DNA samples from male and female descendants of both Josephine Lyon and Joseph Smith have been collected and are being analyzed with the objective of identifying lineage-specific markers..." (Perego, Woodward, Journal of Mormon History, Vol 32, No.2 fn 39). Descendants of Josephine participating in this study have indicated the research is "promising" in confirming Josephine as a daughter of Joseph Smith. The researchers are also hoping to study the other possible children of Joseph Smith and welcome the involvement of descendants.