Should the fast ICE trains pass under the center of Frankfurt or better stop at the Südbahnhof in the south of the city? There are as many opinions as there are experts over this issue.

Nevertheless, Deutsche Bahn will be commissioning a feasibility study to a consultancy company. The report will be ready sometime in 2021. 

DB is for the tunnel because it will not only shorten the connections, it will also increase the capacity in the Frankfurt central station by adding 4 underground stations.

https://www.faz.net/aktuell/rhein-main/frankfurt-streit-um-einen-tunnel-16659176.html