your post is just another proof of your narrow minded view of teeworlds. Teeworlds is NOT only hardcore gaming for people who play teeworlds 6hrs a day.
Tutorials actually are part of the graphical development strategy in the sense of training people who might participate in official development in future. You cannot compare gfx dev with github commits.
I've seen douzens of non-teeish artworks in the past weeks, months and years. I get requests of giving feedback to teeworlds related graphics (logos, web designs, artwork, avatars ...) nearly on a daily basis. Just because you are not experiencing anything related with graphics does not mean it does not take place.
So assuming that my doing explanations are assumptions is just ridiculous. It's just once again you show us you do not have any knowledge about gfx development and community activities.
Gfx dev is possible without code changes. E.g. standardizing teeworlds design (creating teestyle rules), creating new tilesets for new maps, creating new tiles which improve existing tilesets, creating button graphics for the 0.7 layout, creating concepts for new game elements e.g. slopes, website design, new animations, map redesign...
all of this influences the game experience. Go and play 0.2 or 0.3 maps and then go and play 0.6 maps. you will feel the difference. Maybe you won't because you are one of the hardcore gamer who disable all graphical effects. Yeah, well, if you are, it does not make sense to go on.
Go and learn C++ and take part in development. If not, stay calm. Teeworlds is a project of people who have a real life. It's open source and if we are progressing slowly then be glad that there is progress and cheer everytime it's visible. Cheer even more if you can see that it's not dead.
It's funny to demand a graphics dev to create a code tut. You are addressing the wrong person.
In addition it's even more funny to demand such a tutorial for coding but you are not able to see the analogy at graphical development. Kids who do the artwork of today will be the developers of tomorrow. I started drawing crappy artworks, too. So being able to create curved hooks enables them to use the pattern along path technique for other graphics and maybe some official graphics in future.
Antoine de Saint Exupéry: It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away.
Besides - I am the gfx guy!