It has been remarked that "Hoyt may well have taught more Americans about World War II than all other authors in the country put together" and commented about "this prolific author's highly readable oeuvre" (Professor Citino, in his "Death of the Wehrmacht, The German campaigns of 1942" (p.369, note 91 to page 250))
While indeed highly readable, Hoyt's work lacks in accuracy to the point of potentially leading his readers to incorrect conclusions. That is especially the case when the balance in manpower or armaments is misrepresented.
One such glaring example can be found on page 123 about the "phony war" and the prelude to the 1940 campaign in the West: "The numerous German panzers, with their 80- and 88-millimeter cannon, were formidable". That gives the completely erroneous impression that the British and French armored forces were outnumbered and outclassed by the German forces, which in turn leads to an erroneous conclusion as to the reasons for the German victory in May/June 1940.
The balance of power was exactly the opposite of that insinuated by Hoyt as is very well put by for example Omar Bartov in his "Hitler's army, Soldiers, Nazis and War in the Third Reich" on page 12: "When Germany launched its attack in the West, its armored forces were in fact numerically and in some respects also qualitatively inferior to those of its opponents. On 10 May 1940 the Wehrmacht sent into action 2445 of its 3505 available tanks. Facing it were no less than 3383 French, British, Belgian, and Dutch tanks. Moreover, only 725 of the German tanks were of the advanced Panzer III and IV models, and even they had great difficulties in confronting some of the heavy French tanks".
Let me add for those not familiar with WWII armaments that the majority of the German panzers in that campaign were therefore the puny model I, with only two 8 mm machine guns, and the slightly more impressive model II, with one machine gun and one 20 mm cannon. Those German panzer models were outclassed by the French Somua S 35 tank (one of the best tanks of 1940) with a 47 mm cannon and the Char B1 tank with a short 75 mm. The panzer IV (which would become the backbone of the German tank fleet later on and only after significant upgrades in armament and armor in order to be competitive with the Russian T34), with its short 75mm, was competitive against, but not superior to, the B1 and the panzer III, with its short 50 mm, was competitive against, but not superior to, the S35. But both panzer III and IV, already the minority of the German tank fleet at the time, were, at less than 0.7 in thickness, much more lightly armored than either the B1 (at 2.4 in) or the S35 (at 2.2 in). Hoyt's referenced 80 mm gun was not in use with the Wehrmacht tanks but the 88 mm was. However it was introduced with the "Tiger" or Mark VI in mid 1942, a full two years after the 1940 Western campaign.
For more details on armament and armor see for example "Weapons of World War II" from Parragon Books.
The 1940 German victory had nothing to do with a fictional superiority in quantity or quality of the German panzers at the time. Rather consider such factors as organizational innovations, the superiority of the Luftwaffe (at the time) and the high morale of the German troops (who kept fighting despite horrendous losses because of their ideological commitment: see for example W. Murray's introduction to Megargee's "Inside Hitler's High Command": "the lead companies in the crossing of the Meuse...suffered upward of 70 percent casualties but remained in the battle all the way to the south to Stonne three days later").
There are many other errors of this type but listing them here would exceed the allowed length.