PostScript is still useful as a reporting output language (turned to pdf for end-user convenience these days) and for this I felt that the important parts were

PostScript is still useful as a reporting output language (turned to pdf for end-user convenience these days) and for this I felt that the important parts were control of text rendering and placement, placement of blocks of content with respect to each other, and readability of the postscript itself (Because you rarely have a postscript environment that makes it easy to debug). 3 things missing from this tutorial. - but very achievable.