Obviously Michelle Kwan dominated U.S Nationals for a long time. However there was always hype for Sasha Cohen to dethrone Kwan there, but it never happened, with Sasha winning her only title in 2006 when Kwan didnt skate. Even in 2004 and 2005 when Sasha had displaced Kwan internationally and placed above her at worlds, Kwan emerged victorious at Nationals. However Sasha also never skated cleanly at Nationals, the closest being 2002 when she put her hands down on a jump at the end. Kwan always skated perfectly, except 2000 where Sasha would have needed her help to win at that point anyway. What would happened at each of these Nationals year by year to those with a good enough memory had Sasha gone clean. My guesses:
2000- I think they would have given Sasha the win had she not fallen on her last jump over a very subpar Michelle who fell.
2001- Sasha didnt skate, but was never winning this year anyway. She had a mediocre international season and was lowballed by the judges on the grand prix even when she skated well, showing she still had work to do at this point.
2002- Kwan would have won. Sasha's mistake was not that big and she still lost handily and barely took 2nd over Hughes who was about 80% her SLC level at most.
2003- I think they would have given Sasha the win. She had dominated the grand prix and had all the momentum coming in, even if Michelle skated great. Michelle also skated first in the last flight and they had to leave room for Sasha to win. I think Sasha was also still doing the triple lutz-triple toe around now although not sure if she did at Nationals.
2004- Tough to say. My gut feeling is Sasha winning, but Michelle skated amazingly well after Sasha and got 7 6.0s, but she might not have gotten those if Sasha had skated cleanly, and Sasha got a 6.0 from one judge even with a fall and ugly two footed landing.
2005- Sasha wins for sure. Michelle was lackluster, doubling her 2nd triple lutz, and skating to her lackluster Bolero number. Even if skating last she got some candy joke 6.0s after Sasha had faltered though.
So my guess would be Sasha could actually have 5 National titles which would be the same as Michelle is left with, which is amazing to think when in actuality it is Kwan who was so dominant at U.S Nationals. Of course that would require Sasha skating cleanly each time, which would never be realistic anyway, when Kwan who was a far more consistent skater and jumper didnt even manage that.