Re: Partial truth, partial cover up ?
German intelligence were seemingly often rubbish (though not always). They made some terrible errors.
A particularly stunning bit of leading German intelligence, and with it the General Staff, by the nose has been Operation Mincemeat, IMO. At its centre was a corpse with fabricated documents including a letter by the vice chief of the Imperial General Staff to the British Commander in North Africa, detailing an invasion of continental Europe via Greece and the Southern Balkan, with a decoy attack on Sicily. As the German Abwehr after much scrutiny decided that yes, this person and the papers he carried were authentic, a fair bunch of personnel and material were moved from Italy to the Balkan. It took weeks before the Germans actually figured that the Sicily invasion was the real one.
German Intelligence did not just suffer from hubris, they also had the disadvantage that after the Battle of Britain they had way less possibilities to use aerial reconnaissance to corroborate info, as well as less human bodies doing the spying thing.