@amir idea of...

What I would prefer to see is:
1. Develop it
2. Release a stable version as a plugin
3. Let it run for a while and get a lot of feedback from users
4. Tweak and iterate on it at your leisure
5. Finalize the API for other developers (like us) to connect with the new editor
6. Let us time to update our themes and plugins to it
7. Include in core

....makes so much sense in a perfect world.

I said this before....WordPress is going to see a major fail and backlash on the push for Gutenberg; it will happen. Consider the reality of the millions of websites using WordPress, then the plugins, and then the 10's of 1000's themes.

I'm so glad I use Joomla for my own site. I might even start designing themes (templates) for Joomla again if things go terribly wrong later.

Now if the core team ( and Matt ) would just take a breather, sit back for a moment and listen, they might be able to make Gutenberg a success...if done right. Just as Amir posted and many others.