Spontaneity in some areas of writing may be misleading, to the editor and the reader. That’s because spontaneity is a one-off, yet the rest of the time, one’s been doing the run of the mill.
Spontaneity is where the reader was expecting a certain delivery, but is given something out of the ordinary. This might not work for the reader and the publisher. If one were a writer of devotions every week, the reader expects much of the same delivery because that is what sells.
Spontaneity really only works in certain areas, even though it’s “spontaneous”. If one feels like writing something down, it’s spontaneity, and it may work well. One can file it away to publish in the right forum, venue and time.
One may always need to keep in mind that one is writing to a formula or method because this is what the publisher wants. Yet spontaneity can produce some brilliant work…even if it’s one out of the box. I would just write it up and file it away for the right forum or venue, where it would apply, at just the right time, or it comes with a disclaimer : “writer in spontaneous mood, back to regular programming next week” . But one doesn’t want to upset happy campers all the same.