You don’t have to, it’s a solution I built for myself. Page level css dependencies should be in the md. If you want site-wide css then you can put it in baseof.html. If you want css that is template/layout level then using a block in baseof.html and a define in the layout.html should work (shortcodes are for usage inside .md as far as I understand it … I just started using Hugo and I’m not terribly in love with the Golang templating “language”).
A dev or more experienced users please correct me if I’m wrong or please suggest better ways of doing it. Surely this must be a common enough design issue that has been solved before.