The methods of the asanas cannot be incorrect in any case. I think one can blindly refer them.
As stated in the book, it is for the people -
1) Who is planning to have an instructor, then, this book can be used as a reference manual.
2) Who is already practicing yoga and wanted to check if they are doing it correctly.
If you are thinking to start the yoga referring this book, it won’t be easy job and highly not recommended.
Most importantly, not easy to understand the conventions(past chapter references) used in the book, it took me sometime.
Excellent!