Hey im all in for trying to find your own preferred path through theories. And also a balanced training is always better IMHO.
As for upper body muscles and running though, i am absolutely sure they are just deaed weight.
Just look at the 5K olympics finish , those guys look like they couldn't lift a bar to save their lives:

Even the 800m guys , which is more of a long sprint than a short distance race, they are still underdeveloped:

And now that i proved upper body is worthless for running, let's see what i did yesterday for my running training

:
13 December
SS1a : PUSHUPS : 20 @ BW
( 5 reps for 2 sets )SS1b : BENT ROWS : 20 @ 25kg
( 5 reps for 2 sets )SS1 info : 12 rounds
480 total reps, that must be a

or something. Wasn't easy, chest and back could take it but arms were very close to failure at the last sets.