I never said he could run 1:43 "easy". I said that in the next couple of weeks he should record a time of 1:43 something. The more he races (without over racing), the more likely he is to get better tactics and not have to waste metres running wide.
At the end of the day Kaki ran 1:43.5 for running 800m. Wheating ran 1:44.6 (and that will go down as his pb) for about 805.5m. Had he run the allotted distance it would have been sub 1:44. That proves he has the "potential" to run sub 1:44.
That doesn't mean he would have beaten Kaki had he not run wide, it just means he ran wide and therefore ran extra.
I also mentioned the phrase "ideal world". Had Wheating had a rabbit of his own to 500m, going through 400 in 51 flat, and there was only a couple of athletes behind him, then he'd have been under 1:44.