To some extent, this is always the case.
I remember watching the 1980 election returns come in in 1980 on PBS (this was pre-cable), and the facial expression of the news anchor was priceless. Yes, it has always been like this. One difference now is that there are many more information outlets than there were in 1980.
The USC / LA Times tracking poll uses the same methodology as the Rand poll which was #4 in 2012. If we go to the graph, it shows a bump for Trump following the Republican convention and a bump for Clinton following the Democrat convention. So this result isn't surprising. #1 poll in 2012 was IBD/Tipp which had Trump -7 but that was two weeks ago. Pollsters #2 and #3 haven't even started yet -- women's beach volleyball is more important to most until Labor day.
So Trump reassuming a lead is not surprising IMO. The methodology of the USC / Times poll would seem to pick up more "shy" Trump voters than other polls.
The talking heads attribute Trump's polling crash to the Wrath of Khan incident. I beg to differ. It doesn't matter what your race, color, creed or place of national origin is. Khizr Khan is, I think, a horrible poster child for Clinton. If he lived down the street, would you invite him to your barbecue? I don't think that he'd be fun to have as a party guest at all.
