It's a good idea if it works. Which probably doesn't help you at all, sorry
But I need to have a way to end the thing satisfactorily, and I need interesting things to do along the way, or I really can't write it.
I have a few stories partially written sitting around on my hard drive. More than once, I've come back to an old draft and found a way to finish it, years later. I figure, I've got lots of hard drive space, why get rid of stray ideas?
PJ