The French high command were poor, but against a German army in Spring 1939 constrained by a lack of armour to a more conventional assault I suspect they would have been good enough. The Ardennes attack was a massive gamble that could have gone wrong in so many ways and without the considerable upgrades the Wehrmacht obtained between 1938 and 1940 I don't think its possible.
An attack on France in 1938, which Henri seems to imply, is all but impossible. After Poland when Hitler wanted the army to attack France immediately the army resisted because it had used up a large part of its available supplies of fuel and ammo and the armoured units were at seriously reduced strength, in large part because of wear and tear. There is no way that after fighting the Czechs they are going to pivot and attack France in the winter of 1938-9.
There was a book published in 2001 called
Strange Victory by Ernest R. May. The Book argued that the German victory over France in 1940 was anything but inevitable and was due to a whole series of factors. In fact while describing the military events the author makes it clear that at certain times the German attack could have failed. The whole thing was a good deal more chancy than it appears in retrospect.
The book
The Wages of Destruction by Adam Tooze, also makes the same point from the point of view of economics.
Hitler had too repeatedly postpone the attack on France due to lack of preparation and the weather. The initial attack plan was for the main thrust through Belgium. Both the Brits and the French had a plan to deal with that because they expected that. Then Hitler adopted Manstein's plan which used the British / French plan against the British / French.
The German Armed forces were smaller in 1938 than in 1939. While destroying the armed forces of Czechoslovakia their western front would have been very vulnerable and exposed to attack.
It was the above that got the German Generals to insist that Hitler accept Chamberlain's mediation rather than the war Hitler really wanted with Czechoslovakia. The German generals at the time were convinced that war under those circumstances would be disastrous. And despite Henri's bleating it was not "cloud koo koo land" that German generals were planning a coup if Hitler launched a war. Hitler was and they were convinced it would be a disaster under the circumstances. It is simply a fact that before Chamberlain flew to Munich they tried to get in touch with the British. They were rebuffed, ignored.
Hitler emerged from Munich with his prestige enormously enhanced, and in possession of the significant economic resources of Czechoslovakia, (Including its excellent armaments industry), and the extension of Nazis influence into Eastern Europe.
When Hitler invaded Poland in 1939, the German generals now felt they had more or less adequate forces to guard the western frontier and so there was little pressure on Hitler to avoid going to war from this group. Also Munich had discredited, for the time being, any one who contemplated any sort of coup against the regime. So Hitler didn't have to worry about any coup plots. Certainly this time there was no approach to the British or French by disaffected German generals.
As for Chamberlain buying time. Henri in a earlier posting dismissed the point that Chamberlain showed a certain disregard of the possibility of war with Germany by ending the Treaty ports arrangement with the Republic of Ireland. The argument boiled to a post hoc argument that it didn't really make much of difference in the war. Aside from being post hoc. Just how would Chamberlain know this? A great many people including many in the British navy during the war would have vehemently disagreed. It in fact made their task more difficult. (See
History of the Second World War by Basil Liddell Hart, and
Hitler's U-Boat War, by Clay Blair.) In fact the British had plans to invade and occupy the republic of Ireland if things got really bad in the submarine war.
Chamberlain only got more serious about beefing up the British military after Hitler's occupation of Prague, which negated the Munich agreement. Even so he was filled with ideas of continuing appeasement, (Giving Germany Some of Portugal's African colonies for one.), and so even after the occupation of Prague Chamberlain allowed Germany to take the Czech gold reserves held in the Bank of England in London.
And has mentioned before even after Hitler attacked Poland Chamberlain tried to avoid declaring war on Germany and had to be forced to do so by his Cabinet.
