I didn't tell Dr. Speiser that I was the United States until our third email exchange. At that moment, he simply directed me to Dr. Katz instead of answering the one main question I posed to him.
I'll ask you some questions since you're willing to help everyone:
At what levels do the "bad" bacteria have to be diminished to in order for the Streptococcus K12 to be effefctive? Directions from the K12 product suggest a repeat of the high colonisation weekly or bi-weekly, so it's safe to assume that once the bad bacteria recolonizes to a certain level, the Streptococcus K12 bacteria is rendered useless.
If we know that we have to use the chlorhexidine weekly or bi-weekly because the bad bacteria quickly overwhelms the Streptococcus then why not use the chlorhexidine daily to ensure we start off every day with a clean mouth?