And let not forget that the german army, to a large extend because of the restrictions imposed on it by the WW1 peace treaty, was extremily well organised and trained. ...
and had trained their army intensely.
All concepts that go back to Frederick the Great and his father if not earlier. The German army of 1940 owes more to Scharnhorst, Gneisenau and Von Moltke then Gudarian. What win in 1940 was what nearly won in 1914 and was looking to recapture the genius of 1870. The German army was still a decidedly 19th Century army with a core of fast and furious blitzkrieg elements.
Those 100,000 French casualties are a testament to how hard the French fought to hang on. The Germans were lucky and luck had as much to do with 1940 as skill. One of 20th the greatest German strategic concepts was "break through and see what develops"