That reputation was exaggerated by Belton Cooper and has become received wisdom of the unwise kind. BTW, US armored doctrine was not for tanks to fight tanks--that was the role of tank destroyers. Tanks, such as the Sherman, were infantry support weapons. When a Sherman brewed up, it was MUCH more often caused by ammo cooking off. That problem was largely solved by improved storage methods in the mid- to late-war models, which rarely resulted in crew deaths. Yes, lots of Shermans were knocked out by AT fire and mines, but most of them were repairable for return to service, but actually doing so was not often necessary given the abundance of Shermans available--which was one reason for the Allied success on the Western Front. On that note, what is the difference between Germany and the US state of Georgia? (Scroll Down) It took only one Sherman to conquer Georgia.
Crews were unfortunately aware of the Sherman's vulnerabilities. The nickname "Zippo" was not invented postwar. In Patton's "War as I Knew It," he wrote that he had to order units not to stack sandbags on the front slope of the M4s, the measure being both useless and an unwarranted strain on the engines. Ordnance units also took the front plate from salvaged Shermans and welded it on top of the existing armor on operating tanks in the hope of stopping 88s. You can also see applique plates on the sides of Shermans at vulnerable points. But the Sherman was a decent tank built in overwhelming numbers. Only 1,200 Tigers were built. More than 50,000 Shermans rolled off the production lines, including by such familiar names as Alco, Lima, and Baldwin.
No, misinformation did not begin postwar: it was spread during the war before actual analysis of the problem had been done. That and Cooper had an ax to grind.
The virtue of horse transport was that it didn't need fuel, limited though it was by the need for fodder. There are a number of accounts of German troops capturing US vehicles (mostly during the bulge offensive) but being unable to used them because so few of them knew how to drive.
