Donald Trump broke with his campaign's usual course of business Thursday night by holding a town hall event in New Hampshire, a move he and his campaign insisted was not in any way a warm-up for the town hall-style presidential debate Sunday night in St. Louis.

Ahem. Cough. Ahem.

Regardless of his reasoning, the performance Trump put on in front of a very friendly New Hampshire crowd — it was invite-only, conservative radio host Howie Carr served as the moderator, and all questions were submitted in writing in advance — should make any Republican hoping for a bounce-back for the GOP nominee on Sunday night very nervous.

Despite being spoon-fed softball questions — “Are you going to bring jobs back?” — and standing in front of an audience of supporters, Trump struggled to stay anywhere close to a coherent message, repeatedly rambling in answers and seeming more interested in settling personal grievances than talking about the issue at hand.

A few examples:

* Trump began the town hall by insinuating the mic problem he experienced during the first debate was part of a broader conspiracy by the Commission on Presidential Debates. (For the record: While Trump's mic was wonky for the audience in the room, there were no audio problems for the 84-plus million people watching on TV.) In his first answer — about whether he held back in criticizing Hillary Clinton in the first debate — Trump again brought up the microphone, insisting there was a guy in the room “oscillating” his mic.

* Asked by a recent college graduate with a chemistry major how he would create jobs, Trump (1) noted how the “dishonest” media said he was sweating, (2) talked about bringing iPhone manufacturing back to the United States, and (3) pointed out that he has the biggest and best rallies, far better than those of Bernie Sanders. (WaPo's Greg Sargent has a fuller breakdown of Trump's answer here.)

* Thrown a softball about what he would tell conservatives who are not already for him, Trump went on the attack against Sen. Mark Kirk of Illinois. “I guess there’s a gentleman in Illinois who's not doing so well,” Trump said. “And he's not doing well, but, hey, that's his problem.” Sidebar: This is the leader of the Republican Party talking!

* Trump, when asked by an audience member what he would do “to convince Hispanics who were deceived by President Obama, Hillary Clinton and the biased media to vote for you,” first noted that Hispanics love him, then segued into the story of a rally he held in Las Vegas that had a “tremendous crowd of people. Hispanics, Latinos they like to be called, in that area, you know that, right?” Um . . .

* When Carr asked Trump whether he was upset — as had been reported — about Mike Pence not vigorously defending him from attacks in the vice-presidential debate, Trump went into an extended attack on CNBC's John Harwood and CNN's John King. Here it is, courtesy of the indefatigable Sopan Deb of CBS:

Pretty remarkable, right? Trump's lack of message discipline is made all the more amazing when you consider that even as he was riffing in New Hampshire, his top aides were peddling a narrative that Trump was buckling down and would be more serious and prepared for Sunday's town hall debate than he was for the first faceoff with Clinton last week on Long Island. Here's the first paragraph of Jenna Johnson's piece, which posted at 10 p.m. Thursday night, on the plan for a new Trump:

Donald Trump and his allies signaled Thursday that he is ready to move past the controversies that have dominated the 10 days since the first presidential debate and that he will try to stay focused on policy, not attacks, at the second debate on Sunday.

Er, okay.

Here's the thing [clears throat]: There is no new Donald Trump. What you see is what you get. Trump is a living, breathing example of how all of the best-laid plans go out the window after you get punched in the face. Even if he knows what he should do — or at least what people like his campaign manager Kellyanne Conway need him to do — in this second debate, Trump's performance in New Hampshire on Thursday night shows that he is simply incapable of executing a plan that runs counter to his freewheeling, stream-of-consciousness approach.

He just doesn't have it in him. To expect a different Trump at this point in the campaign is to believe something against mountains of evidence to the contrary.