I'm a little curious; people keep saying here that crushing the BEF at Dunkirk would have been a key part of a German victory, but how practical was it? To my understanding, Kluge and Rundstedt ordered the brief halt May 21 in order to preserve their mobile forces and permit them the chance to recuperate in the wake of Arras, a course of action Hitler confirmed on the 24th after meeting with Rundstedt. It also gave them two days to move up infantry forces on foot to ensure the attack went through in a great big push. Most of this came to light well after Liddel Hart's seminal work with his primary sources being many of these generals, who were themselves quite keen on shifting as much blame as they could to Hitler. It certainly served Rundstedt and Guderian well, to name two, to blame as much as they could on Hitler to preserve the "purity" of the Wehrmacht; being deceased as well as vilified, he could hardly defend himself.
Beyond this, the idea that Hitler thought that permitting the BEF to escape would permit peace was not entirely clear. It does seem rather odd, however, considering that orders that went out on the 24th called for the annihilation of the pocket and the soldiers within. What it feels like to me is that Rundstedt decided he needed to consolidate his forces for a moment before moving forward again; hence, he ordered the halts on the 15th and 21st, and though there's less documentation on what went on during the meeting, by this precedent likely played a role in ensuring another halt on the 24th-25th.
Also, fun detail, since the mention was brought up of it: if Hitler hadn't meddled at all, France would have lasted much longer and may not have fallen at all. The OKW was never enamored with Manstein's little notion of a push through the Ardennes. They wanted a direct punch through Belgium as had been conducted in World War 1, and they were concerned that concentrating their armored forces in such a manner would make them impossible to supply or maneuver (accurately, but I digress). Manstein and Rundstedt won out because they went over Halder's head to Hitler, who loved the idea and gave it his own seal of approval. Halder being Halder, he immediately reversed his own coat and decided the idea was brilliant all along. It seems to me that the OKW's intentions would have smashed right into the Dyle Line and French reserve forces, instead of cutting them off as occurred historically. Indeed, this is part of the reason why Hitler was able to so effectively and so dangerously interfere later; he had already pulled one rabbit out of his hat.
