That is simply not true. If it is 16 segments or less, it can be re-issued as an e-ticket. I know - from personal experience. However, the trick is finding someone who actually knows how to do it. When someone tells you it can't be done, persist - it can.

Last time we did it was at NRT - after the lengthy usual discussion at the counter at NRT and a phone call or two, it couldn't be done ... until they found the right person in the Tokyo ticket office, who obviously said "no problem". Had to let them send the tickets in to Tokyo, who then delivered the revised/ electronic itinerary to our hotel (along with some refund vouchers for some taxes).