I just did a quick and dirty, back of the envelope analysis on the relationship between the 100m and 200m using the top 250 100m/200m/400m athletes of all time and came up with:
Estimated 200mt = -1.0634(100mt)^2 + 22.835(100mt) - 101.92
This gave Bolt 19.24 based on 9.58 and 19.34 based on a 9.62
Tyson: 19.54 based on 9.71 and 19.67 based on 9.77
Obikwelu: 19.85 based on 9.86
And my own PB within 1/100th of a second.
It predicts that Bolt would require a 9.48 to break 19 seconds.
The model goes out the window, when you look at guys that were predominantly 100m runners and only occasionally ran the 200m (over estimate) or vice versa (under estimate), this could be because they never maximised potential in one or the other.
Before I cop a heap of crap for this and get smart alec remarks about a correlation between the number of bolt and his reaction time - I know it’s rubbish, but its a bit of fun and least this one doesn’t pretend to be deterministic.