The real reason why Trump distanced himself from 'Send her back' chants?

Trump-haters are rejoicing in what they see as a major fissure separating President Trump from his base over the Greenville, North Carolina rally's crowd chants of "send her back!" CNN carefully counted out 13 seconds between the beginning of the chant and Trump's resumption of his speech, thereby pinning responsibility for the chant on Trump.

So, when Trump stated his disagreement with the sentiment, after being asked about it during an impromptu Oval Office media availability…

KARL: "Mr. President, if I may, when your supporters last night were chanting 'Send her back,' why didn't you stop them? Why didn't you ask them to stop saying that?"
TRUMP: "Well, number one, I think I did. I started speaking very quickly. It really was a — I disagree with it, by the way. But it was quite a chant. And I felt a little bit badly about it, but I will say this: I did, and I started speaking very quickly. But it started up rather fast, as you probably noticed."
KARL: "You'll tell your supporters never to say it again?"
TRUMP: "Well, I would say that. I was not happy with it. I didn't agree with it. But again, I didn't say — I didn't say that, they did. But I disagree with it."
KARL: "But they were echoing what you said the first week, basically, that they should go back."
TRUMP: "Well, I don't think, if you examine it, I don't think you'll find that. But I disagree with it. Anybody else?"

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