The only "impromptu" part of the proceedings was tens of thousands who were not involved in the planning joining groups like the Oathkeepers and Proud Boys who had discussed for days how to strategically plant weapons thruout DC. It's part of the Conspiracy charges against them...
"The government’s long-standing theory in the case is that the extremist group came prepared for violence on Jan. 6 and stashed firearms just outside of Washington, DC, which they could easily access via a “quick reaction force” or “QRF.” Until this week, though, prosecutors had shared little evidence other than text messages that referenced a special force. Wednesday’s hearing featured the government’s most comprehensive presentation to date that such a plan was at least partially put into action."
A judge ordered Kenneth Harrelson, indicted in the Oath Keepers conspiracy, to stay in jail after finding “strong evidence” that he posed a danger to the community.
www.buzzfeednews.com
There were a hardcore group of planners and there were a much larger group of people who ended up at the Capitol as almost a reflexive action. But one of the main reasons people who should have known better got swept up, is because many of them were convinced that Pence could actually stop the election certification and chose not to do so. THAT type of misinformation being disseminated is directly attributable to Trump and his minions, and numerous speakers belabored that point during the speeches...
But even before the speeches, people associated with the militias were walking among the crowd and advising them to head to the Capitol after Trump's speech. That is captured perfectly in the NYT video, and is a perfect example of how the militias ramped up the crowd to unwittingly join them in what they had already planned.
Plenty of Oathkeepers types were already at the Capitol and no doubt took note of how lax thelma security was and the absence of serious law enforcement. It's not a coincidence that every one of the 8 or so breaches of the Capitol were initially provoked by dedicated militia types who incited others to join in...
Admittedly Jordan Klepper is a comedian, but he was in DC on Jan 6. And he captured video of plenty of militia types and extremists heading to the Capitol before Trump's speech was even over.
Trump's speech lasted till about 1 pm, while you can clearly see militia types organizing and heading to the Capitol en masse before 11 am. They were people on a mission who hoped the masses would join them. With help from provocateurs and Trump urging people to "walk to the Capitol" that's exactly what happened...