Here's Paul Shaw writing in this month's Print magazine:
The misspellings, typographic infelicities, and poor writing that plague Jan Tschichold, Designer might be overlooked if Doubleday's analysis of Tschichold's work for Penguin was of high caliber. But his writing is pedestrian and often beset by run-on and fragmented sentences. Furthermore, sentences in the text are frequently repeated word for word in the captions and, on occasion, elsewhere in the text.
Ouch. Here's the Amazon link:
Jan Tschichold, Designer: The Penguin Years
Naturally, the only review there is five stars and calls the book "a seminal and impressive contribution to the history of publishing . . . ."