On Dramatic Arcs

During my senior year of university, a whopping eleven years ago, I borrowed The Street Where I Live from my grandmother.  It's an autobiographical work by Alan Lay Lerner that covers the writing and staging of My Fair Lady, Gigi, and Camelot. (I'm not really into musicals but I was interested in the look at the creative process and drama thereof.)  Lerner observed that up until the musical became retroactively associated with the Kennedy presidency, the cohesive first half of Camelot was considered the strong act, and the more chaotic second half deemed dramatically weaker.  After JFK, the comic first half was the "weak" arc, the tragic second half the "strong" one.  Context matters.

There is a thread on Serenes Forest about what makes for a good story in a video game but it is filled with bullshit and not worth the read.  

Anyway, I'm interested specifically about what makes the second half of FE4 fall flat in a dramatic sense.  The falling action of FE2 is good-- and the twist of the penultimate Big Bad is fantastic.  The "second act" of FE3-- Book II in general-- is very good, IMO one of the better storylines in Fire Emblem.  But the Celice part of the Jugdral saga appears IMO to be the "weak half" of a game that is often lauded for its story.  

( So what's up with that, then? )