A. Wariner never tried or trained for the 800m when he was the best in the world at the 400m. He had fallen way off his game by the time he did.
B. The analogy between 400/800 and 3000/5000m is invalid. There is a very good 3k-5k correlation and the all-time list for the two events are quite similar.
Here are the 12 3k guys under 7:26, along with several multi-appearances:
1 7:20.67 Daniel Komen KEN 17.05.76 1 Rieti 01.09.1996
2 7:23.09 Hicham El Guerrouj MAR 14.09.74 1 Bruxelles 03.09.1999
3 7:23.63 Jakob Ingebrigtsen NOR 19.09.00 1 Eugene 17.09.2023
4 7:23.64 Yomif Kejelcha ETH 01.08.97 2 Eugene 17.09.2023
5 7:24.00+ Jakob Ingebrigtsen NOR 19.09.00 1 Paris 09.06.2023
6 7:25.02 Ali Saïdi-Sief ALG 15.03.78 1 Monaco 18.08.2000
7 7:25.09 Haile Gebrselassie ETH 18.04.73 1 Bruxelles 28.08.1998
9 7:25.16 Daniel Komen KEN 17.05.76 1 Monaco 10.08.1996
10 7:25.47 Grant Fisher USA 22.04.97 3 Eugene 17.09.2023
11 7:25.48 Telahun Haile Bekele ETH 13.05.99 4 Eugene 17.09.2023
12 7:25.54 Haile Gebrselassie ETH 18.04.73 1 Monaco 08.08.1998
13 7:25.79 Kenenisa Bekele ETH 13.06.82 1 Stockholm 07.08.2007
14 7:25.87 Daniel Komen KEN 17.05.76 1 Bruxelles 23.08.1996
15 7:25.93 Thierry Ndikumwenayo BDI 26.03.97 1
By going down to 35 5000m performances, I got almost all the top 12 3k guys, except for Ndikumwenayo. #1 Cheptegei has never made a good 3k attempt, so he's not on the 3k list above. Bekele, #2, has a 3k best of 7:25.79, 5k 12:37.35. #3 Haile Gebrselassie ran 7:25/12:39. Daniel Komen 7:20/12:39.74. Telahun Haile Bekele has 7:25.48/12:42.79. Yomif Kejelcha has 7:23.64/12:41.73. Aregawi is just below the 3k list at 7:26.8 with his 12:40.45. Grant Fisher is 7:25.47/12:46.96. Jakob is #3 at 3k, 7:23.63 (7:24.00 enroute to 2M WR also) and 12:48.45 three years ago in a sit and kick race, but he split 7:21 for his last 3k of the 2M and as winner of the last two World Champs 5000m, he certainly would destroy his 5000m pr in a wr attempt. So, there's plenty of reason to think that a guy who can run 8:00 2M indoors and close a 7:42 in 25.2 can run well under 13.
1 12:35.36 Joshua Cheptegei UGA 12.09.96 1 Monaco 14.08.2020 2 12:37.35 Kenenisa Bekele ETH 13.06.82 1 Hengelo 31.05.2004 3 12:39.36 Haile Gebrselassie ETH 18.04.73 1 Helsinki 13.06.1998 4 12:39.74 Daniel Komen KEN 17.05.76 1 Bruxelles 22.08.1997 5 12:40.18 Kenenisa Bekele ETH 13.06.82 1 Saint-Denis 01.07.2005 6 12:40.45 Berihu Aregawi ETH 28.02.01 1 Lausanne 30.06.2023 7 12:41.61 Joshua Cheptegei UGA 12.09.96 2 Lausanne 30.06.2023 8 12:41.73 Yomif Kejelcha ETH 01.08.97 1 Oslo 15.06.2023 8 12:41.73 Jacob Kiplimo UGA 14.11.00 2 Oslo 15.06.2023 10 12:41.86 Haile Gebrselassie ETH 18.04.73 1 Zürich 13.08.1997 11 12:42.18 Hagos Gebrhiwet ETH 11.05.94 1 Monaco 21.07.2023 12 12:42.58 Berihu Aregawi ETH 28.02.01 2 Monaco 21.07.2023 13 12:42.70 Telahun Haile Bekele ETH 13.05.99 3 Monaco 21.07.2023 14 12:43.02 Selemon Barega ETH 20.01.00 1 Bruxelles 31.08.2018 15 12:44.39 Haile Gebrselassie ETH 18.04.73 1 Zürich 16.08.1995 16 12:44.90 Daniel Komen KEN 17.05.76 2 Zürich 13.08.1997 17 12:45.01 Mohamed Katir ESP 17.02.98 4 Monaco 21.07.2023 18 12:45.09 Daniel Komen KEN 17.05.76 1 Zürich 14.08.1996 19 12:45.71 Jacob Krop KEN 04.06.01 1 Bruxelles 02.09.2022 20 12:45.82 Hagos Gebrhiwet ETH 11.05.94 2 Bruxelles 31.08.2018 21 12:46.02 Jacob Krop KEN 04.06.01 5 Monaco 21.07.2023 22 12:46.21 Telahun Haile Bekele ETH 13.05.99 3 Oslo 15.06.2023 23 12:46.33 Nicholas Kipkorir KEN 29.09.98 1 Roma 09.06.2022 24 12:46.53 Eliud Kipchoge KEN 05.11.84 1 Roma 02.07.2004 25 12:46.79 Yomif Kejelcha ETH 01.08.97 3 Bruxelles 31.08.2018 25 12:46.79 Jacob Krop KEN 04.06.01 2 Roma 09.06.2022 27 12:46.81 Dejen Gebremeskel ETH 24.11.89 1 Saint-Denis 06.07.2012 28 12:46.91 Yomif Kejelcha ETH 01.08.97 1 Zürich 31.08.2023 29 12:46.96 Grant Fisher USA 22.04.97 2 Bruxelles 02.09.2022 30 12:47.04 Sileshi Sihine ETH 29.01.83 2 Roma 02.07.2004 31 12:47.20 Mohammed Ahmed CAN 05.01.91 1 Portland 10.07.2020 32 12:47.53 Hagos Gebrhiwet ETH 11.05.94 2 Saint-Denis 06.07.2012 33 12:48.09 Kenenisa Bekele ETH 13.06.82 1 Bruxelles 25.08.2006 34 12:48.25 Kenenisa Bekele ETH 13.06.82 1 Zürich 18.08.2006 35 12:48.45 Jakob Ingebrigtsen NOR 19.09.00 1 Firenze 10.06.2021
A. Wariner never tried or trained for the 800m when he was the best in the world at the 400m. He had fallen way off his game by the time he did.
B. The analogy between 400/800 and 3000/5000m is invalid. There is a very good 3k-5k correlation and the all-time list for the two events are quite similar.
Here are the 12 3k guys under 7:26, along with several multi-appearances:
1 7:20.67 Daniel Komen KEN 17.05.76 1 Rieti 01.09.1996
2 7:23.09 Hicham El Guerrouj MAR 14.09.74 1 Bruxelles 03.09.1999
3 7:23.63 Jakob Ingebrigtsen NOR 19.09.00 1 Eugene 17.09.2023
4 7:23.64 Yomif Kejelcha ETH 01.08.97 2 Eugene 17.09.2023
5 7:24.00+ Jakob Ingebrigtsen NOR 19.09.00 1 Paris 09.06.2023
6 7:25.02 Ali Saïdi-Sief ALG 15.03.78 1 Monaco 18.08.2000
7 7:25.09 Haile Gebrselassie ETH 18.04.73 1 Bruxelles 28.08.1998
9 7:25.16 Daniel Komen KEN 17.05.76 1 Monaco 10.08.1996
10 7:25.47 Grant Fisher USA 22.04.97 3 Eugene 17.09.2023
11 7:25.48 Telahun Haile Bekele ETH 13.05.99 4 Eugene 17.09.2023
12 7:25.54 Haile Gebrselassie ETH 18.04.73 1 Monaco 08.08.1998
13 7:25.79 Kenenisa Bekele ETH 13.06.82 1 Stockholm 07.08.2007
14 7:25.87 Daniel Komen KEN 17.05.76 1 Bruxelles 23.08.1996
15 7:25.93 Thierry Ndikumwenayo BDI 26.03.97 1
By going down to 35 5000m performances, I got almost all the top 12 3k guys, except for Ndikumwenayo. #1 Cheptegei has never made a good 3k attempt, so he's not on the 3k list above. Bekele, #2, has a 3k best of 7:25.79, 5k 12:37.35. #3 Haile Gebrselassie ran 7:25/12:39. Daniel Komen 7:20/12:39.74. Telahun Haile Bekele has 7:25.48/12:42.79. Yomif Kejelcha has 7:23.64/12:41.73. Aregawi is just below the 3k list at 7:26.8 with his 12:40.45. Grant Fisher is 7:25.47/12:46.96. Jakob is #3 at 3k, 7:23.63 (7:24.00 enroute to 2M WR also) and 12:48.45 three years ago in a sit and kick race, but he split 7:21 for his last 3k of the 2M and as winner of the last two World Champs 5000m, he certainly would destroy his 5000m pr in a wr attempt. So, there's plenty of reason to think that a guy who can run 8:00 2M indoors and close a 7:42 in 25.2 can run well under 13.
1 12:35.36 Joshua Cheptegei UGA 12.09.96 1 Monaco 14.08.2020 2 12:37.35 Kenenisa Bekele ETH 13.06.82 1 Hengelo 31.05.2004 3 12:39.36 Haile Gebrselassie ETH 18.04.73 1 Helsinki 13.06.1998 4 12:39.74 Daniel Komen KEN 17.05.76 1 Bruxelles 22.08.1997 5 12:40.18 Kenenisa Bekele ETH 13.06.82 1 Saint-Denis 01.07.2005 6 12:40.45 Berihu Aregawi ETH 28.02.01 1 Lausanne 30.06.2023 7 12:41.61 Joshua Cheptegei UGA 12.09.96 2 Lausanne 30.06.2023 8 12:41.73 Yomif Kejelcha ETH 01.08.97 1 Oslo 15.06.2023 8 12:41.73 Jacob Kiplimo UGA 14.11.00 2 Oslo 15.06.2023 10 12:41.86 Haile Gebrselassie ETH 18.04.73 1 Zürich 13.08.1997 11 12:42.18 Hagos Gebrhiwet ETH 11.05.94 1 Monaco 21.07.2023 12 12:42.58 Berihu Aregawi ETH 28.02.01 2 Monaco 21.07.2023 13 12:42.70 Telahun Haile Bekele ETH 13.05.99 3 Monaco 21.07.2023 14 12:43.02 Selemon Barega ETH 20.01.00 1 Bruxelles 31.08.2018 15 12:44.39 Haile Gebrselassie ETH 18.04.73 1 Zürich 16.08.1995 16 12:44.90 Daniel Komen KEN 17.05.76 2 Zürich 13.08.1997 17 12:45.01 Mohamed Katir ESP 17.02.98 4 Monaco 21.07.2023 18 12:45.09 Daniel Komen KEN 17.05.76 1 Zürich 14.08.1996 19 12:45.71 Jacob Krop KEN 04.06.01 1 Bruxelles 02.09.2022 20 12:45.82 Hagos Gebrhiwet ETH 11.05.94 2 Bruxelles 31.08.2018 21 12:46.02 Jacob Krop KEN 04.06.01 5 Monaco 21.07.2023 22 12:46.21 Telahun Haile Bekele ETH 13.05.99 3 Oslo 15.06.2023 23 12:46.33 Nicholas Kipkorir KEN 29.09.98 1 Roma 09.06.2022 24 12:46.53 Eliud Kipchoge KEN 05.11.84 1 Roma 02.07.2004 25 12:46.79 Yomif Kejelcha ETH 01.08.97 3 Bruxelles 31.08.2018 25 12:46.79 Jacob Krop KEN 04.06.01 2 Roma 09.06.2022 27 12:46.81 Dejen Gebremeskel ETH 24.11.89 1 Saint-Denis 06.07.2012 28 12:46.91 Yomif Kejelcha ETH 01.08.97 1 Zürich 31.08.2023 29 12:46.96 Grant Fisher USA 22.04.97 2 Bruxelles 02.09.2022 30 12:47.04 Sileshi Sihine ETH 29.01.83 2 Roma 02.07.2004 31 12:47.20 Mohammed Ahmed CAN 05.01.91 1 Portland 10.07.2020 32 12:47.53 Hagos Gebrhiwet ETH 11.05.94 2 Saint-Denis 06.07.2012 33 12:48.09 Kenenisa Bekele ETH 13.06.82 1 Bruxelles 25.08.2006 34 12:48.25 Kenenisa Bekele ETH 13.06.82 1 Zürich 18.08.2006 35 12:48.45 Jakob Ingebrigtsen NOR 19.09.00 1 Firenze 10.06.2021
Virtually everyone on your list is a 3k specialist or a 5k runner moving down. Kerr is a 1500m man moving up. There is almost zero reason to believe he will ever run well under 13:00. He has never broken 13:20 and only runs 70 miles a week. For reference, Jakob runs 110-120.
You can´t compare the jump from 400m to 800m (some can do; it some can´t) with the (little) jump from the 2 miles to the 5000m.
Some 400m runners are natural sprinters with low aerobic capacity which makes the shift to the 800m very "expensive".
On the other hand: To run a 8 min 2 miles you must have a very high aerobic capacity and that capacity will help you to very good 5000m too. Just ask Gebrselassie and Bekele (see my post above).