bifevo wrote: there would be a big difference between a system that I would use for my own gaming groups and something that I intended to seriously develop.

This is a quote from bifevo's first post over at Modern-Day Divinities RPG - Develop or Discard?. It raised some questions in my mind that I wanted to ask, but didn't want to clutter up bifevo's thread with.

These questions are:
To bifevo, what differences do you think would arise based on whether you develop this for your group, or for publication of some kind?
Do other designers (and would be designers) make this distinction?
How many of you who have finished games out there originally developed them for use with your own groups or clubs?
Those of you who did, what changes, if any, did you make to your game before you had a publishable version?
Did the original game and group serve as merely a first draft and playtest group?

I'd be interested to hear anybody's thoughts on these or related questions.

what differences do you think would arise based on whether you develop this for your group, or for publication of some kind?

Good question. One of my pursuits has been, in past years, technical writing. One of the things there is "write to the level of understanding of the audience." So, the difference between developing for a group and the world are substantial:
1. If I write for a particular gaming group, then I am writing for an audience that knows me personally and that I know well. I would not have to carefully look over my writing and ensure that it does not fall into the pitfall of "something only my gaming group would understand," as some publications have from time to time.
2. Much, much less background and world text to write. Since I would most likely GM the game myself, all of this is nicely stored in my head, and my concept is not foreign to me. However, this concept would be foreign to others, and I would need to walk them through the basics of the game world.
3. Layout, editing, etc. Essentially, for personal play, most of this doesn't matter. For even a free public release, if this is done poorly then no one is going to care what you wrote, but only instead how it was written. While popularity is not the end goal of all designers, few people want to slave over a game and release it to the world only to have it dismissed because "the layout isn't so great, and there's no artwork in it either."

As I see it, these are the key points. The audiences have vastly different knowledge given about me, have very different needs for what needs to be written down, and are quite different in how that must be presented. As a result, there are a handful of big differences in what I would write for my gaming group. It would likely be dramatically shorter. It would contain more slang, phrases unique to those I know personally, and concepts where I can say "it's like X but with the following differences" where X is a shared idea or experience. As I would GM it, I would not have to write up a formal world background, histories, important characters, and sample scenarios common to many released games. Finally, it would have virtually no time given to layout, artwork, and other "publishing"-type concerns.

Hope this helps. Thanks for the good question. (and for not hijacking the thread - most thoughtful)