I've not gotten a straight answer. I assume it is a pet project kind of situation, or trying to justify the data warehouse project as a whole, but I really don't know the real driver to do this.
There wasn't even a lot of transformation going on. It was just... strange. I witnessed some true eldritch horrors like Python calling R calling a shell script that called the mysql client, which wrote data to a temporary file that was eventually read by the great-grand-parent python script.