I feel the need to clarify my "yes" response to the OP: What I meant was in keeping with what StaciaKane said, which boils down to: At some point, "just write it" is the only advice to be given.
You may need to plan XYZ, or outline ABC, but "at some point" ya gotta actually write stuff. It's dead easy to get wrapped up in "planning", to the detriment of real story construction. And we seem to get a hell of a lot of thread-starter questions here that take the form of "How much description is too much? How many characters are too many? How much dialogue is too much? How many 'r's in a manuscript are too many?', etc.
To which the only possible answer, ever, is 'I have to see the writing.' To which I often get the impression doesn't yet exist.
I developed this bias as a result of frequenting a local writer's group for several years a while back. The two most prolific producers of material to be critiqued were 1. A man who longed to writer 'technothrillers', and had planned, via detailed outline, a series of forty-some, one of which was partly done. What he showed of it was utterly unreadable, filled to overflowing with implausible action, impossible action, anachronistic references, horrid grammar, and characters as substantial as morning mist in the sunshine.
The second was a man longing to write epic high fantasy novels, and all he ever showed was backstory world-building.
At some point, just write the damn story. Then, if you want it critiqued, by all means get it into the hands of critiquers (SYW here is a good place for that). All the nitpicky questions you may have can be answered only in the context of actual story.
I teach a university-level composition course, based entirely upon students actually writing. It is titled 'Methods of Written Communication', which I consider a great course title, and I try to construct the course to meet that title. I know that other instructors who teach this course rely on tests and quizzes, because I've seen some of them. I particularly recall on instructor's quiz on the use of commas, left behind in the same classroom where I teach. Dreadful waste of time. I teach punctuation and grammar and all the other nitpicky tools useful to make writing work, but I can judge every student's ability to use those tools by assessing the writing assignments they turn in. I don't need to give quizzes on such things.
Those principles also apply to my view on creative writing of the sort people who participate in AW are interested in. So . . . at some point, just write it. In general, I suggest doing that sooner, rather than later.
Overplanning has probably produced more lifeless wooden story narrative than anything else. Too many inexperienced writers think that if they just get everything planned out well enough, they can then 'write by number', filling in all the bullet points with prose. Maybe some can (Terry Brooks comes to mind, from a forum at a conference some years ago in which I saw him discuss his heavily-outlined approach). Great if it works. Others, not so much (John Saul comes to mind, from the same panel in the same conference).
For me, story-writing is a journey. Sometimes I know where I want to end up, sometimes I don't. Sometimes I change my mind about the former idea, once I get to actually writing. In the second case, where I finish comes along as the journey progresses.
My favorite example of the latter, in my own experience, is from my best unpublishable novel. I had two possible conclusions in mind as I wrote, to the point that I began to rough out each possibility. I had some way to go to get things to either of those conclusions, and worked on finishing that stuff, when suddenly (yes, I know you all detest that word, but in this instance it fits, literally), the story was concluded. I recognized it the moment I hit that point, and it was a feeling both of surprise and great satisfaction. Neither of the two intended endings was either necessary or appropriate. I was done.
Some people who have read the manuscript haven't liked that ending, and have told me so, and why, and I have respected and appreciated those comments. I took them on board, and gave them considerable thought. And, ultimately, I still think my ending is most appropriate. It satisfies the story, if not every reader. I never would have got it if I'd been playing write-by-number from a detailed outline.
For my currently near-complete unpublishable novel, I have already written the concluding chapter. I'm currently quite happy with it. I need a major transitional event, to get there, and am having problems working that out. As a consequence, I might . . . might, mind you . . . scrap that conclusion in favor of something else. Point is, I'm open to doing that. Maybe some comet will arrive, unexpected, from the literary Oort Cloud, and alter my thinking. It's happened before. I'm open to it happening again.
But that is only possible because I wrote, not knowing what was ahead on that night highway, seeing just as far as the headlights allowed, watching for poorly-marked curves, oncoming traffic, moose emerging from the woods to cross the road.
I just wrote it.
caw