Since the Book is not 'the factory default stack of Rails' but rather the Rails "way" we certainly do have an opinion about what is considered the most popular and efficient way of building Rails apps. This does mean we use HAML throughout the book, because honestly, we all think its a better choice. Personally, since we converted to HAML at Astrails several years ago, I cringe every time I have to deal with ERB. Its just too verbose and it doesn't present the structure as obviously as HAML. Same for the rest of the 'opinions' in the book. YMMW
Since the Book is not 'the factory default stack of Rails' but rather the Rails "way" we certainly do have an opinion about what is considered the most popular and efficient way of building Rails apps. This does mean we use HAML throughout the book, because honestly, we all think its a better choice. Personally, since we converted to HAML at Astrails several years ago, I cringe every time I have to deal with ERB. Its just too verbose and it doesn't present the structure as obviously as HAML. Same for the rest of the 'opinions' in the book. YMMW