As an ex Telstra tech that was part of a team that installed the optical regenerators between the South Australian border and Darwin the the 1980's and early 1990's I can tell you for sure that the cable does degenerate The run between Katherine and Darwin had to be totally replaced after only about 18 months, the "buffer" as its called that covers the glass fibre was shrinking and the glass fibre was adversely effected, no amount of higher power optical laser transmitters would overcome this At the time there were optical regenerators every 50 kilometers Nothing lasts forever Fiber is a backbone technology and thats were it belongs - not a last mile technology I've been working in this field since 1975
