I did not mean to imply that I think McLaughlin can run 155.5 now. I mean if she got bored of destroying everyone in the 400mh and switched to the 800m instead of the 400m, and trained like an 800m runner, where would she end up? I think better than 1:58. But I don't see her in the 1:54s.
If Kersee is talking about her breaking the 400m WR, she'd have to be at least a 1:56 talent I think. Her 200m time is 22.39 and 400m 50.07. Whereas Alison Felix at 21.69 and 49.26 is 0.7 faster at 200m and only 0.8 faster at 400m. So she's more of an endurance runner than Felix, but Felix was a sub 11 100m runner so that doesn't really tell me much.
I know that it won't happen so it's just mindless speculation. I've been on the board pretty consistently during the WCs and haven't seen another thread about this during the championships. I know it gets annoying seeing these kind of threads (like back in the Jeremy Wariner days), but when someone annihilates a WR the way she just did, it kind of changes the picture. I'm just curious what other people think. Honestly, even though it might get boring for her winning by that much, she's smartest to just continue dominating her event. The wider general public will only understand her as a megastar if she continues to completely dominate. If she switches to 400m and loses sometimes or wins in "only 48.80" the average dummy who only tunes in for the Olympics and who needs Gail Devers to tell them what to think will think she's not as good as she used to be.
Also, as for 400m hurdlers switching over to 800m, Brandon Johnson (USA) was a 48.59 400m hurdler in 2005, and later switched and ran 1:43.97 for the 800m in 2013. It's not a super common thing, but common enough that you should have heard of it happening if you are any kind of track and field fan.