Echo tropes

[Qara-Xuan Zenith]

If this was covered somewhere and I'm forgetting, I'm sorry. It's getting hard to keep track of everything I've read in the past few days.

I remember a few of us debated a couple times whether each echo had one specific set-in-stone trope that we were supposed to identify, or whether the point was for us to "identify" a trope by reading into a comic where none in particular had been intended, or (most likely) some middle area between the two. I'm wondering to what extent were either of these views correct?
And was it ever really annoying when we just weren't getting the intended trope? Or were you ever pleasantly surprised (or just plain surprised ) by a different trope we came up with instead?

[Dana]

We did have a set-in-stone trope for each comic. That said, if you found a way to incorporate something equally valid and in the comic into your story, we were gonna go with the best story.

[Tom]

There were times when a winning fic used a different trope than we had intended.