For those unfamiliar with the show, it is a twist on fairy tales, throwing fairy tale characters into our world. The way the story is told is by alternating between what's going on in our world (in the town of Storybrooke) and what happened back in time in the fairy tale world (the Enchanted Forest). The portions from the past always help to further the plot of the part of the story being told in the modern world. It also follows a ton of different characters' stories.
The original version of Across the Stars followed only Sara Watson. The time frame of the story was straightforward and covered only the brief period of time the Watsons were on Emoria. I didn't really keep track of when I wrote different parts of the story, but I have been able to piece together through various memories somewhat of a time line of the writing of that book. And so I am fairly certain that Once subconsciously inspired me to delve into the past of certain characters and deepen the plot through the use of multiple main characters and backstories. I'm not terribly skillful at strategically revealing plot points in the flashbacks and such, but it does serve to deepen the plot and make the story more interesting.
In The Experiment, I did stay in the same timeline, but I had broken away from the single point of view and thus was able to tell the story more fully by telling all relevant parts of it.
For the Time Captives trilogy (Creighton Hill), I am continuing to use the Once Upon a Time Effect. I am enjoying, as I rewrite Creighton Hill, delving into the past of the older Hubbards and discovering what happened to them in the time before the youngest ones arrived, and just what their history with Toarna is. This could not be accomplished effectively without this technique, and I love the depth it is adding to the story.
I have come to love the complication the Once Upon a Time Effect gives to a story and can't imagine Across the Stars or Time Captives without it. It just shows even structure of storytelling can be influenced by what one reads and watches!