Record book mingling is a shameful attempt at keeping the cake (pretending athletics has been cleans) and eating it too (having world records constantly broken).
The dope fest called sub 2hr mara attempt beckons and here' tucker's take from pacing angle (dope implications have been discussed before). I agree with him that actually breaking the barrier is highly unlikely - the 2.03s are already full *** stuff and done quite recently. Also find it a reasonable guess that a DNF is as likely as the best case scenario, ie 2.02 for kipchoge.
Would be interesting to see the first graph disaggregated for per and post epo eras, split roughly from 1990 or so. But even as it stands, one could hazard a guess that blood doping (refills and epo, say, post 1990)has allowed for a more even pacing strategy than in prior eras.
https://sportsscientists.com/2017/05/sub-2-hour-marathon-attempt-pacing-strategy/
To put a cherry on top:
"Here's a nutty statistic ahead of the #breaking2 attempt: In the 90 fastest winning marathons ever, a 5km segment faster than 14:13 has only been run 10 times. That's 10 out of 720 segments for those 90 race winners. The target pace to break 2 hours this weekend is 14:13 per 5km. They'll have to average for a marathon what has only been done for a single 5km segment ten times in the fastest 90 marathon victories ever."