The depth and clarity of the advice and the effort put into presenting it work as solid credentials in this case. The author is clearly a “doctor” of design.

The depth and clarity of the advice and the effort put into presenting it work as solid credentials in this case. The author is clearly a “doctor” of design. Look how well those those graphics get their message across, whilst also matching the style of the text. That takes a real steady hand (both literately and figuratively).