You are fixating on one tiny point which isn't really that important within OP's ... errm "opus".

Why not critique the entire work?

Anyway:

I borrow 100 from someone. I am now in debt and they are in credit - to balance, both are 100.

However, they require a return on investment - usury: 10 for 100 (or a 10% margin - call it what you like).

When I take out my loan, I am in debt for 110 and they are in credit for 100 with a promise of 10 later. So we have some accounts - my one account is 110 in debit (I borrowed 100 and promised to pay 10 on top) and they have two accounts - one for the principal (100) and another for the 10 interest. To me, in this case, the principal and interest are part of the same account but to the lender they are separated out because the interest is probably taxable as income.

However, it might be the case that I can set off my debt or the interest on my debt against some tax. In that case I will maintain two accounts - the principal and the interest.

All those interests will also end up in additional accounts related to probably banking.

I've probably pissed off a few accountants with my choice of terms but in the end I do understand how fiat money works.

What gets on my tits is assertions such as "People who don't understand ..." with no working.

Yeah CPA here. On the day you take out the loan you're not in debt 110, you are in debt 100; you would accrue interest expense over the term of the loan. What if the lender called the loan day 2 for some reason? You wouldn't pay 110, probably just 100 plus one day of interest. Goes back to fundamental definitions of financial statement elements. Liabilities are present obligations.

Anyways, recognizing the interest over time would debit an expense account and credit some liability account... Could be the same account as the loan or could be an interest payable account, doesn't really matter in the context of the example.

Also you would not be "in debit"; the liability is on the credit side of your balance sheet.

What gets on my tits more is people who are pretty bright in one field (hacking) thinking that entitles them to just brute force their way through reasoning about some other field (finance) that in their arrogance they think is simpler.

You can't have taken a class on finance and/or accounting and passed it. This is 101 material, literally. Read the CPAs take.

And, in my initial comment i explicitly point out the error - the interest amount should not be there. People don't tend to show the working for zero * x = zero. This misunderstanding of a very fundamental piece makes any material on this topic by this author not worth reading. It might render everything they write not worth reading because they also don't know where their circle of competence stops.