every situation is different. a horse like hard spun was pretty consistent at a high level.. he COULDVE won more races IF horses like street sense, curlin, etc (who were faster overall) werent his opponents. The fact is that Hard Spun, even when he did lose, could get the distance! Best example is the derby where he ran his best effort at the time.. ONE faster horse beat him. When u compare him to that crop overall he was a superb horse. Distance was never an issue for this horse.
I really think something that goes under-rated is the perspective on how a race lays out in general. Hard spun or any speed horse or closer is a good example. In a shorter race theres more likely to be faster fractions and much different scenarios then longer ones. Blind Luck has recently run great against horses going ONE turn closing and winning but at 2 turns the adjustment had to be made within the horse. As much as she finally flew down that stretch in her 2 turn race she still lost the race. If that race was a bit longer it doesnt mean she would have won though.. the idea is the there would have been a completely different situation and set up going longer for other horses as well as her... its equal.. so all we can go by is the thoro number to determine who should win that race within a horses pattern.
If a horse is racing consistent neg 2s as an example at 9F and is going 10F today and we are handicapping we have to assume for the most part that going two turns and the extra 1F the horse will run about the same and should beat horses who are running consistent 1s or slower..especially at this top level.. There are many other factors to considered but the idea is that a neg 2 effort will beat a 1 effort.. thats why we buy the thorographs. Hard Spun as well as many others have done this and run their top efforts derby day within their respected lines(as you can see with my example) sooo many times and DISTANCE or the extra 1F meant nothing.. what mattered was that the horses they were racing against were faster than them overall and those horses were beaten based on that (or of course ground loss, tu, etc..) alone. There are even MORE examples like summer bird, curlin, etc as weve mentioned before who improved even more over time and eventually developed to become champions in time... once again ALL of these horses have something in common and that is they go all go TWO turns.. once that is established the faster horses usually take the cake.