I'm not sure I agree on your last point; some of the younger, less print-bound designers I've worked with have a good understanding of the difference between pr

I'm not sure I agree on your last point; some of the younger, less print-bound designers I've worked with have a good understanding of the difference between presentation and semantics, and have been often enough annoyed by sites which look just dandy at 1920x1080, but are unusable on a phone, to have a burning desire not to produce more of the same. Stipulating that point, though, perhaps the solution is to keep designers at a higher level of granularity -- to have them produce designs for "large screen", "small screen", "mobile", "print", &c., including general ideas of how body text shall appear, but leave the more granular detail to someone who's not so much wedded to pixel-perfection, but instead understands that the same content will necessarily look different when differently rendered, and who can understand and accommodate those differences to produce a result that works well across all of them.