I used to be alarmed by the things Trump said. What I've come to realize is that he is working politics the way he would work real estate. Say what the buyer wants to hear, but when the time comes to work a deal, start with an opening bid that gives you room to negotiate.

Leading up to the deal, if the person hates the Patriots, he'd say that he's glad Tom Brady is finally going to have to sit his 4-game suspension. If the person loves the Patriots, he'd probably focus on the fact that a number of owners in the NFL want Brady to play, and the NFL would be foolish to ignore them.

More than likely, he doesn't care, and those sorts of details are irrelevant. What matters to him are big picture issues: get out of nation building, secure our border, renegotiate trade agreements, and protect America's interests. The big picture goal for him to even be able to do these things is to become president.

Right now, he needs to be the uncontested GOP candidate, so he mentions hotbutton issues that resonate with Republican voters. Vaccinations, protecting the rights of Christians, Global Warming is a myth, etc. I don't think that he really cares, and because he doesn't care, he sees these things as inconsequential details. "Honesty" is irrelevant to him when it comes to these sorts of details. One day his favorite color is blue. The next day, it's green. Because it's irrelevant to him, he doesn't see it as being dishonest.

Now that his nomination is nearly secure, he's starting to focus on the general election. Transgender rights? His response is that he doesn't know if any of his employees are transgender, and he doesn't care. It's none of his business, and they can use whatever bathroom they want. Regarding the environment, I'm betting he'll soon say that any sort of plan to deal with it is irrelevant when countries like China are polluting the environment with no concern for the consequences. You want a cleaner world, let him renegotiate trade deals and bring manufacturing jobs back to America where we have much more control over emissions than China. Change "global warming" to "pollution," and he gets a whole lot more people to agree with him. The details are just semantics, so he'll argue he isn't really lying about anything.

TL;DR: He doesn't really care about the details so long as he is getting what he wants in the big picture. Since the details aren't important to him, he'll talk about them in whatever way will benefit him the most.