A and C: the issue is not potential problems that get discovered during the inspections and require costly repairs. Who wants to continue flying with a corroded airframe? The issue is that performing the SIDs will cost a lot of money.
With Part M, these SIDs are generally considered to be mandatory service instructions in EASA land. The Cessna twin SIDs became mandatory here, although they were stripped down a bit through alternate methods of compliance.
This can really bite us...