Alexandria, Virginia (CNN) The fourth day of Paul Manafort's trial blended tax documents with a witness' astonishing confession of guilt. Prosecutors are well into presenting hundreds of documents that they say show bank fraud, failure to disclose foreign bank accounts and tax crimes.

Here are four takeaways from the court action Friday:

1. Bank fraud smoking guns?

In a courtroom, lawyers have various tools to make their points: video screens to show evidence, pointed questions to elicit certain answers and witnesses to speak about their firsthand knowledge of the alleged crimes. On Friday, the three legs of the evidentiary stool built a solid moment for the prosecutors.

The jury read damning email messages and documents to support the bank fraud charges. A witness said she had discussed creating fake documents with Manafort and longtime deputy Rick Gates, then sent the faked documents to a bank on their behalf.

She also testified that she knew her tax firm had fudged a loan amount so a then-broke Manafort could save up to a half-million dollars in taxes.

It's the closest this trial has come to smoking guns so far.

2. Foreign bank account repetition

All three financial professionals who worked for Manafort -- the bookkeeper Heather Washkuhn and the accountants Philip Ayliff and Cindy Laporta -- sat through the same minute-long inquisition that appears to form the core of the prosecutors' foreign banking charges. Did you know Paul Manafort was affiliated with these companies? the prosecutor begins. He says one corporate name at a time, ending after 14 or 15. The witness says "no" to each.

Those are the offshore companies that prosecutors have already established paid for Manafort's personal excesses or "lent" him money.

The other thing prosecutors have established? That each of the financial professionals told Manafort explicitly and multiple times that he would break the law if he did not disclose his foreign accounts. He did not make those accounts known to them, all the witnesses said.

3. White-collar crime challenge

White-collar crime cases are notoriously hard to prosecute. This case has had hours of tax code explanation and tax returns, corporate financial accounting and the intricacies of loan, income and mortgage tax deductions.

Many a government attorney has lost a corporate financial case or had a mistrial because evidence became too dense, boring or confusing for the jury to follow.

Will Manafort's jurors face a similar result?