How effectively does George Eliot use flashback?

Eliot's use of flashbacks allow the plot to progress and provide a deeper understanding for us, her readers, to understand Marner and his actions. For example, in Part One, the author flashed back a full fifteen years to provide us with Silas' time in Lantern Yard. Through this flashback, we come to understand Marner's emotional state, and the fact that is has been colored by betrayal.