Thank you for your response. To clarify, I'm not an elitist that rejects cartoons and informal style. For example, I think the "Calculus for Dummies" with the cartoons is a good math book.
I'm also not really not talking about the visual "clutter" that others complain about either.
Cartoons are fine but I prefer that the drawings/illustrations really impart knowledge or insight rather than "decorate" a book's page like wallpaper.
For example, I looked at "Head First Networking". Using Amazon's "Look inside" feature to browse some pages:
- page 1: the clipart of the man and woman and the thought bubbles do not reward the user with quality knowledge in relation to the space they take up
- page 19: the clipart of the tourist with the arrows and thought bubble does not actually teach a networking concept
My point is: just because a book has cartoons & unserious style doesn't mean it has good presentation of teaching. It might be a suboptimal book that just happened to use cartoons.
Another way to put it: Comics can be a very powerful way to illustrate concepts but their power is underutilized in the Head First books. The cartoons are often "jokes" instead of teaching.
>which, to many people, reads as non-serious
Similar to cartoons, I have similar complaints about "conversational style" that many authors think helps with pedagogy but it really doesn't. (You can explain things terribly while using a conversational tone, and likewise, explain things clearly with a serious tone.) I'll save that criticism of that for another essay.
 https://www.amazon.com/Calculus-Dummies-Lifestyle-Mark-Ryan/... https://www.amazon.com/Head-First-Networking-Brain-Friendly-...