Excerpt from my latest Sasstrology post (please leave comments on the Sasstrology site):
"The sextile is a misunderstood aspect in synastry. It’s considered by some to be interchangeable with the trine, but so “soft” that it doesn’t have much impact in the connection between two people. But the fact remains that sextiles are one of the Ptolemaic aspects. To ignore them is to overlook part of the relationship’s story. Having said that, how much weight do they actually carry? Not all aspects are created equal, and it would be a mistake to assign sextiles the same amount of strength as a conjunction (or a trine)."