@simon
If you are using your own GDD as a programmer then your not only a programmer but a designer as well... That's two jobs.
And you don't have to have completed games to be a game designer.. that's just so others can know you're good at designing games without looking at your GDD.
@JBadams
A GDD doesn't prove anything but neither does previous completed games. Previous completed games (good ones) says that you can create good game designs but doesn't prove your next one will be good.. Just increases the likelyhood. A GDD says a lot even if you don't have previous completed games.
It's like... Would you buy a share in the stock market just because it's been climbing in the past? (previous games)
Or would you take a look at the GDD and see if it's a potential good game (Analyze the share in stock market to see if there's an incoming reversal or the company is having trouble etc)?
Both is better than none but I would for sure go with the GDD if I had to chose just one of these.
a GDD doesn't say anything about a persons design skills, things that look good on paper rarely is as good in practice which is why game designs tend to change drastically during development, hand the same GDD to two different teams and you might end up with completely different games possibly even in different genres (Changes can be very drastic and good designers are probably more able to make drastic changes if they spot an opportunity for it) (id Softwares Quake for example is an excellent example, it started out as a fantasy RPG but ended up a sci-fi action shooter because the designer wasn't afraid to make drastic changes when testing revealed opportunities or flaws) (And the designer was obviously also good enough to realise that the game would be better if the changes were made)
This is why a GDD is nearly worthless as a basis to hire someone on, If i hire a designer i'm not interested in what starting point he can provide, i'm interested in the results he can deliver especially if there are technical or practical constraints to what can be done (For indies this is always the case) , a solid SC2 level says more about a persons design skills than any GDD ever will.
I wouldn't call myself a game designer even though i have designed games since its not what i primarily do, just like i don't call myself an artist or a composer even though i've drawn pictures, built 3d models and composed some music tracks. I would consider it extremely disrespectful towards those who actually dedicate themselves to those jobs.
Edit:
I think we are partially talking about different things aswell, If you are a designer trying to form a team then having a GDD is far more important than if you are a designer trying to join a team.
If you intend to join a team then your GDD will most likely not be used at all as the team has allready gone beyond that point (It might be a starting point for a second project though) and any decent team will be far more interested in what you can do with an existing concept.
If you intend to form a team then things get really rough as you have to not only sell your design, but also your ability to produce a finished product.
This is why most successful indie teams start out as 1 - 3 man projects, You cannot reasonably expect to attract talented strangers to your project unless it is at a stage from which the finish line is clearly visible.
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