Stoppit Smith wrote:
Ryan Hall.
Easily.
First marathoner that made the fastest African runners really have to be on their A+ game.
Nobody mentioned previously had the level of African competition thrown at him like Hall
After getting to the current end of the thread, I noticed it was Meb vs Hall for a while. I have to agree with the Hall side. Look at Shorter. He never raced Mosop on the very best day of his career. He certainly never beat guys like that: either Mutai, Haile, Tergat, whoever. Nor would have have been within several minutes of any of the top East Africans, given that they are in their primes (as they were when Hall raced them) of the last few decades.
Meb 'appeared' in a lot of races. (Appeared was the term used by the Meb Fan Club referring to Rio. He really was the only USA embarrassment in that race.) He would have been dead last in some if there weren't paid amateurs behind him, like NYC. Meb beating weak fields is less impressive than a 4th place minutes faster on the same course. Keep in mind Rupp's watered-down-by-Nike-who-is-the-primary-funder-of-the-race Chicago was quite a bit slower than Hall's 2:08:08. That's just another of Hall's races, certainly not one of the first 3 any fan would mention.
OK, Meb vs Hall - I just told you where I come down there - is a non-sequiter to the real answer. Sure, Hall and Meb are both top-10, as is JBS. The answer to the OP's question is Deena. No handicapping nor adjustment needed. No percentage for shoes: oh, her times is WORTH how many ever minutes (it's slightly less than a minute-and-a-half for both Kipchoge and Bekele, that test has already been done) faster. None of the old 'but this was in 1976!' arguments apply. She is LITERALLY the American Record holder. Not withstanding decades passing, shoes, lighter wristwatches, or any of the changes the thread has gone on about, no American - neither native-born nor Kenyan mercenaries (another debate entirely, admittedly, hashed out in many threads) has run faster.
Deena Kastor.