German isn't actually very agglutinative: it's an inflected language with some agglutination. Pure agglutinative languages tend to have very regular stress - see point 3. But I could make the guess that Sumerian poetry worked on vowel length instead of stress and then do exactly what you suggest for vowel length (which mathematically makes no difference). I'll certainly try this when I get some time - paper submission deadline for conference proceedings on Wednesday, and I'm away at an EPSRC GRADschool from tomorrow morning until Sunday night.