I'm thinking about Sydney and I'm also thinking about Femke Bol, the latter, with her deceptively outrageously easy looking stride.
1:49.00/800 seems preposterous for a woman, but so did a 2:11:52 marathon for a woman a few years ago.
I think it's possible.
I think women like the above two could do it with specific training.
Think Alberto Juantorena and Alberto Cruz.