Michael Goulder's comprehensive book lays out his lectionary theory concerning the nature of the gospels especially as it relates to their formation in correspondence to the historical Jewish cycle of Old Testament readings. Goulder's ideas are compelling, and certainly as he lays them out it seems very probable that the construction of the synoptic gospels follows a particular set of Old Testament readings. Specifically, the discussion about Matthew's gospel following the Jewish festal cycle illustrating the almost flawless way that Matthew follows the themes and readings of the yearly festivals across his Gospel.
Goulder's alternative to the usual source-critical commentary is refreshing to read and would surely be of benefit to take seriously and consider in greater depth.