An Runner wrote:
OP, think of it this way... The fatties at the local Fleet Feet Sunday run are able to waddle for 20 miles, so something is wrong with you if you cannot. (...)
I guess it all depends on your goal. If you are just racing on the track, there really is no need to go any further than 100 minutes.
a regular and quite fast long run shows of course a good fitness level. but it´s not the omnipotent formula for everyone. as written above: it all depends on your goal, and it depends on the individual frames.
for example, a quite slow and really long "long run" might be too unspecific for middle distance guys. meanwhile i know some superfast guys running usually no more than 70mins, rarely 80mins, especially when doing doubles.
personally speaking i also cancelled the long runs in support of faster 9-10 milers or elongated workouts.