The Frankfurt experience was reported at ICANA.
The 3.2 degree approach :
ICANA 2013: Experience with the steeper approach angle of 3.2 degrees - YouTube
Is the amount of work worth the limited effect ? the audience asks. The rigid adherence to CDA giving rise to noisier approaches was interesting.
The multi-segment 4.49 degree approach trial :
ICANA 2013: Steeper Approach -- a research project of DLR and Airport and Region Forum - YouTube