I just found time to read the article!
I was very curious about how he would define substance!

He found a definition! An impressing simple and good one!

And his explanations about the relation of style and substance and their different functions in game design are much worth!

http://www.puppenheim.org/
http://www.wuerfels-welt.de
Old Game Tutorial: http://www.puppenheim.org/MITutorial.zip
Free Game Editor: http://puppenheim.org/AlienalsWeihnachtsmann.zip
http://www.puppenheim.org/blender_starting_main_settings.txt