Going the other way is terrible too. I had to work on making text in pdfs that our software generated selectable and searchable. PDF simply doesn't have any way to communicate the semantics to the viewer, so things like columns, sidebars, drop letters, etc. Would all confuse viewers. It didn't help that every pdf viewer uses its own heuristics to figure out how text is supposed to be ordered. Ironically, Acrobat was one of the worst at figuring out the intended layout.