> A weakness of the Q source hypothesis is the absence of any textual evidence despite extensive scholarly efforts to find it. The entire hypothesis is based on statistical and literary analysis and inference. It adds complexity to the synoptic problem by introducing an additional layer of tradition, transmission, and composition, which may not be warranted given the available evidence (or rather lack thereof).
Wouldn't Occam's Razor suggest that the Farrer hypothesis is most likely true?
Edit: Or, maybe I should just continue reading to the end first:
> On the other hand, it would also make for a more complex explanation than other scholars have proposed, violating the principle of Occam’s Razor. Alternatively, Mark could have been the source for Matthew, and Matthew for Luke, which is a much simpler explanation than the Q hypothesis.