"Any athlete who can run 20 flat...has at least 10 flat ability...wind etc..."
--Not necessarily. Just a few examples: Pietro Mennea 19.96 & (10.15). Kostas Kenteris 19.85 & (10.15). Michael Johnson 19.32 & (10.09).
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"Borzov only ever did what it took to win a race" & "times did not interest him"
--Sprints happen so quickly, with little room for error, that I find such comments attributed to Borzov to be self serving.
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"Borzov was always super controlled"
--That he was because his technique was almost perfect. That also gave the illusion that he wasn't trying hard. He, better than most sprinters, counter intuitively understood that wasteful motions and pressing too hard would actually slow one down (typically over-striding). He learned the art of running relaxed (proper breathing being the key). Another words "less is MORE."
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"At that period Americans never really performed well outside of the US.....which makes me think some of the so called sub 10s in the states come into question...and wind readings have been queried many times"
--The little competition that took place internationally (pre professional era) was mostly national competitions, regional championships, and the Olympics. The few international meets outside of those events usually took place in the US and a few Western European (Zurich Weltklasse) meets. 1969 to 1971 Borzov never faced the very best Americans (e.g. John Carlos). Admittedly it wasn't the strongest period, those years, in American sprint history, but then the focus was on the NCAA and the Olympics every 4 years. 1973 onwards, American sprinters dominated the ever growing international meets.
There were only 3 "so called sub 10s" up till Munich; Hines Olympics 9.95 electronic & 2-9.9s hand timed US Olympic trials). The hand times were of course inherently inaccurate, but that would include all hand times, not just those "2-9.9s," at a time when almost all races were hand timed. Wind readings to this day are still problematic (In Race) as conditions vary lane to lane and from start line to finish.
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"One thing is a fact Borzov was like Bolt today...head and shoulders above the rest over a 6 yr period from 69 through to ,75"
--71 & 72 (ranked #1 in 100 both years, #2 in 200 in 71 & 1st in 72 Track & Field News) were his two most dominant years where he went undefeated. 69 & 70 (ranked 5th & 2nd in 100, un-ranked in 200) he was up & coming. 73 he barely ran (un-ranked 100 or 200) and was smoked by the Americans when he did, and gradually got back in competitive form in 74 (5th-100, un-ranked 200) and in 75 (3rd-100, 8th-200).
In conclusion, Borzov was dominant in 71 & 72 and was in the conversation of Worlds fastest human in 70 and top 3 in 75.
1976 he was ranked #3 in the 100, non-ranked in the 200 and would never again be ranked in the top 10.
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"Remember this guy came back from double Achilles surgery to win bronze in 76....10.14.....same time as winning time in 72....which obviously means borzov had so much more in the tank in 72"
--No he didn't have double surgery Achilles prior to 76 nor ever. You may be confusing his ankle problems in 79 when he retired rather than continue training for Moscow in 80. He said the cumulative effects of training on hard tracks made it too painful to continue training. Regardless he was no longer World Class (77 onwards)at that point. Comparing anyone 4 years apart is like comparing 2 different athletes, so doesn't really give a good analysis, and at best a speculative analogy.
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"Regardless of sub 10 sub 20 ability.....athletes are really only remembered for what they achieved not what coulda,,,woulda....shoulda...."
--I agree, which is my point that imagining what we think someone can achieve means nothing. If Borzov was capable of running sub 10 he had 12 yrs from 68 to 79 to accomplish that which is plenty of time.