I will have to disagree. If you had a dog who could speak with a vocabulary of more than a dozen words (earth) and you found another dog that could speak with a vocabulary of more than a dozen words (this new planet) the implication is the ability of a dog to speak with more than a dozen words is more common than previously thought and it would not be a stretch to assume within the millions of dogs out there, you would be able to find more since you already found two.
I agree, one does not a trend make, but two does imply more. (At least in nature)
Hmmm. There's my flaw. :)