Ivan, I'm not sure where you are headed with that post. Lets look back at history:
On 6 October, Hitler made a peace offer to both Western Powers. Even before they had had time to respond, on 9 October, he also formulated a new military policy in case their reply was negative: Führer-Anweisung N°6,
This plan was firmly based on the seemingly more realistic assumption that Germany's military strength would still have to be built up for several more years and that for the moment only limited objectives could be envisaged. They were aimed at improving Germany's ability to survive a long, protracted war in the west. Hitler ordered a conquest of the Low Countries to be executed at the shortest possible notice. This would stop France from occupying them first, and prevent Allied air power from threatening the vital German Ruhr area. It would also provide the basis for a successful long-term air and sea campaign against the United Kingdom. There was no mention in the Führer-Directive of any immediate consecutive attack to conquer the whole of France, although as much as possible of the border areas in northern France should be occupied.
While writing the directive, Hitler had assumed that such an attack could be initiated within a period of at most a few weeks, but the very day he issued it he was disabused of this illusion. It transpired that he had been misinformed about the true state of Germany's forces. The motorized units had to recover, repairing the damage to their vehicles incurred in the Polish campaign and further more ammunition stocks were largely depleted.
Franz Halder, the chief of staff of the German Army, presented the first plan for Fall Gelb on 19 October, the pre-war codename of plans for campaigns in the Low Countries: the Aufmarschanweisung N°1, Fall Gelb.
Aufmarschanweisung N°1 was based on an unimaginative frontal attack, sacrificing a projected half a million German soldiers to attain the limited goal of throwing the Allies back to the river Somme. Germany's strength for 1940 would then be spent; only in 1942 could the main attack against France begin.
On 29 October, Halder proposed a second operational plan, Aufmarschanweisung N°2, Fall Gelb, featuring a secondary attack on the Netherlands.
General Gerd von Rundstedt, the commander of Army Group A, disagreed with it. Its fundamental flaw was that it did not conform to the classic principles of the Bewegungskrieg, or "maneuver warfare" that had been the basis of German operations since the 19th century. A breakthrough would have to be accomplished that would result in the encirclement and destruction of the main body of Allied forces. The logical place to achieve this would be in the region of Sedan.
On 10 January, a German Messerschmitt Bf 108 made a forced landing at Maasmechelen, north of Maastricht, in Belgium. Among the occupants of the aircraft was a Luftwaffe major, Hellmuth Reinberger, who was carrying a copy of the latest version of Aufmarschanweisung N°2. Reinberger was unable to destroy the documents, which quickly fell into the hands of the Belgian intelligence services. On 30 January, Aufmarschanweisung N°3, Fall Gelb, was issued which essentially conformed to the earlier versions.
On 2 February, von Manstein's plan was brought to Hitler's attention. On 17 February, Hitler summoned von Manstein, General Rudolf Schmundt (the German Army's Chief of Personnel) and Alfred Jodl to attend a conference. Hitler sat and listened, abandoning his habits of interrupting and launching into monologues. In the end, he agreed to all of von Manstein's suggestions. The next day he ordered the plans to be changed in accordance with von Manstein's ideas. They appealed to Hitler mainly because they offered some real hope of victory. Hitler recognized the breakthrough at Sedan only in tactical terms, whereas von Manstein saw it as a means to an end. He envisaged an operation to the English Channel and the encirclement of the Allied armies in Belgium, which, if carried out correctly, could have a favorable strategic outcome.
Aufmarschanweisung N°4, Fall Gelb, was issued on 24 February. The bulk of the German officer corps was appalled by the plan, and they called Halder the "gravedigger of the Panzer force".
Even when adapted to more conventional methods, the new plan provoked a storm of protest from the majority of German generals. They thought it utterly irresponsible to create a concentration of forces in a position where they could not possibly be sufficiently supplied, while such inadequate supply routes as there were could easily be cut off by the French. If the Allies did not react as expected, the German offensive could end in catastrophe. Their objections were ignored. Halder argued that, as Germany's strategic position seemed hopeless anyway, even the slightest chance of a decisive victory outweighed the certainty of ultimate defeat implied by inaction.
Fast forward to 13 May, the German XIX Corps forced three crossings near Sedan, executed by the 1st, 2nd and 10th Panzer Divisions, reinforced by the elite Großdeutschland infantry regiment. Instead of slowly massing artillery as the French expected, the Germans concentrated most of their air power (as they lacked strong artillery forces) to smash a hole in a narrow sector of the French lines by carpet bombing and by dive bombing.
The disorder that had begun at Sedan spread down the French lines. At 19:00hrs on 13 May, the 295th regiment of 55th Infantry Division, holding the last prepared defensive line at the Bulson ridge, was panicked by the false rumor that German tanks were already behind its positions. It fled, creating a gap in the French defenses, before even a single German tank had crossed the river. This "Panic of Bulson" also involved the divisional artillery. The Germans had not attacked their position, and would not do so until 12 hours later, at 07:20 on 14 May. Still, the French had several hours to launch a counter offensive before the Germans consolidated the bridgeheads, but failed to attack soon enough.
Recognizing the gravity of the defeat at Sedan, General Gaston-Henri Billotte, commander of the First Army Group whose right flank pivoted on Sedan, urged that the bridges across the Meuse be destroyed by air attack. That day every available Allied light bomber was employed in an attempt to destroy the three bridges, but failed to hit them while suffering heavy losses. Some 44 percent of the Allies bomber strength was destroyed.
Heinz Guderian, the commander of the German XIXth Army Corps, had indicated on 12 May that he wanted to enlarge the bridgehead to at least 20 kilometers. His superior, Ewald von Kleist, ordered him on behalf of Hitler to limit his moves to a maximum of 8 kilometers before consolidation. On 14 May at 11:45, von Rundstedt confirmed this order, which implied that the tanks should now start to dig in. Guderian was able to get to von Kleist to agree to "reconnaissance in force", by threatening to resign. This vague terminology allowed Guderian to advance forward effectively ignoring von Kleist's order to halt.
On 15 May, in heavy fighting, Guderian's motorized infantry dispersed the reinforcements of the newly formed French Sixth Army in their assembly area west of Sedan, undercutting the southern flank of the French Ninth Army, which collapsed, and surrendered en masse. The 102nd Fortress Division, its flanks unsupported, was surrounded and destroyed on 15 May at Monthermé bridgehead by the 6th and 8th Panzer Divisions. The French Second Army had also been seriously mauled and had rendered itself impotent. The Ninth Army was giving way because they also did not have time to fortify their lines. Erwin Rommel had breached its defenses within 24 hours of its conception. This allowed the Rommel to break free with his 7th Panzer Division. Refusing to allow his division rest and advancing in light and darkness, the Ghost division advanced 30 miles (48 km) in just 24 hours.
On 23 May, Günther von Kluge proposed that the German Fourth Army, which was poised to continue the attack against the Allied forces at Dunkirk, should "halt and close up." Seeing the Allies were trapped in the city, von Rundstedt agreed with von Kluge. In the German Fourth Army diary it is recorded on 23 May "will, in the main, halt tomorrow [May 24] in accordance with Colonel-General von Rundstedt's order." General Walther von Brauchitsch, commander in chief of the German Army, disagreed with his colleagues and wanted to continue the attack against Dunkirk by putting the Fourth army under Bock. The disagreement went to Hitler, who overruled Brauchitsch and agreed with stopping action against Dunkirk.
Thus, I find no deliberate plan to isolate the BEF, nor any deliberate plan to conduct the war in the manner in which it actually happened. Due to several fortuitous circumstances and German officers disobeying their direct commanders the battle of France would have played out much differently as would Dunkirk had the Germans not halted for 3 days.