The word tantra, states Patanjali, means principal, main. He uses the same example of svatantra as a composite word of sva (self) and tantra, then stating svatantra means one who is self-dependent, one who is his own master, the principal thing for whom is himself, thereby interpreting the definition of tantra.
As DNA Circles get larger and more DNA matches are delivered, more people are connecting into the DNA Circles, which results in more New Ancestor Discoveries, but with a decrease in accuracy. So, we are updating the criteria to make it more conservative and increase the accuracy of New Ancestor Discoveries.
You have to compare your results with others for them to be useful. Both FTDNA and Ancestry sponsor groups or projects where people in the same haplogroup can exchange information and maybe even find an ancient connection. But Y-DNA and mtDNA are intended to check ancient bloodlines, 10,000-50,000 or so years ago.