I know Lauren - and maybe the racing is a side issue - there's evidence out there for and against. It's hard to make the comparison with ladies as they weren't running distance until recently. But the men running in the 60s and 70s had an approach that produced far more depth over 5K - marathon in those days than we do now.
http://www.thepowerof10.info/ranking...ex=M&alltime=y
The half marathon all time rankings show other than Farah, we have to go to 20th place before we get to a time recorded this century. In fact Tomas Abyu in 50tyh place all time is the fastest in the last 10 years.
Gebrselassie is phenomenal - but he won the world junior 5K and 10K in 1992. In 93 he won the Senior 10K and silver in the 5K when he was only 20.
He was probably on 100 mile weeks and with some intense work thrown in and we are still talking potential for athletes in their mid 20s.