The upside of bad textbooks

Mainstream introductory economics textbooks have so many weaknesses it's hard to know where to start listing them. But for the sake of context let's just have take a scatter gun approach. So, in no particular order these weaknesses include:
1) the pretense that people are rational and disciplined.
2) the pretense that more things make us happy.
3) the pretense that markets are mostly perfectly competitive.
4) the pretense that the economy can be studied in isolation from the political and legal systems.

Don't worry. I haven't run out of weaknesses. But my point in this blog actually isn't to discuss the weaknesses per se. Rather it is to wonder whether bad textbooks aren't a blessing in disguise for the good teacher. After all, they provide a wonderful focus for critical commentary. And in the process  of critiquing the textbook, perhaps students become aware that just because something is written in a textbook, that doesn't mean to say it is true. Perhaps the process of having a bad textbook, and a lively critique of the book in class, provides critical awareness of how the subtle process of persuasion operates.

What do you think? Is there an upside to bad textbooks?
TM