Scott,
Your basic point–display– is well taken, however your comments on the
quality of scanned images are not.
It is true that a 150 dpi scan prints like a "fine" resolution fax (in
itself a visible difference from a "standard" one), but a 300 dpi image is
quite readable, and a 600 dpi scan on a 600 dpi printer should (I've seen them)
come out looking as good as a 300 dpi original.
Obviously there is a problem with expecting the customer to print a
whole book before reading, but in specific applications (compendia of data
sheets eg) where you're basically replacing microfilm, collecting images on a
ROM and having the user print 6 pages and go back to their desk is a very cost
effective thing to do. (And a lot better looking than the average microfilm
blowback)
Frank