Agreed there is a ton on the line for both of these guys. And I dont see a compelling argument that either is more than a very slight favorite over the other.
The whole "Kerr is stagnant at 3:29" thing seems a bit silly. IIt's not like he's been stuck there for 8 years, he first ran 3:29 in 2021 and is obviously a much better runner now by virtue of his WC gold, Pre Classic win, and indoor 2mi WR. He also ran 3:45.34 for the win in May, which converts to a 3:28.79 according to WA tables. Given his success at peaking for world champs/olympics in the past, it's pretty reasonable to expect he's capable of a second+ faster if he's following Jakob. Is he capable of 3:26 high/3:27 low? Much bigger question mark, but it would also take an exceptional performance for Jakob to lead his way to that time. That's what makes this so spicy and hard to predict. How fast can Jakob truly go when soloing from the front, and how well can Kerr hang on to Jakob's best?
Or maybe Jakob doesn't push from the gun and puts more faith in his kick in a 3:28+ race. He'll have to be significantly better than he was the last two WCs for that to work, but he very well might be.
Either way, it's gonna be an amazing race.