The replacement of the debit-normal and credit-normal account structure with simple use of positive and negative numbers is not unprecedented in computerized double-entry accounting systems (ledger-cli and it's ports and offshoots do this, too); it's quite natural since the credit-debit system was itself a hack around the medieval European resistance to negative numbers and a way to reduce subtraction operations by grouping everything into addition of columns of positive numbers and then one substraction of the two column totals.
> Surely some of their customers have competent accountants maintaining the business's books. This unasked-for effort will make their job harder.
Uh, why? It's trivial to present information tracked as positive debits and negative credits in two positive columns; keeping the internal architecture of the database this way should be irrelevant to the end user, it's just avoiding using a hack designed to optimize the experience of people doing a manual process with medieval European technology and attitudes towards negative numbers in an automated backend where none of the problems it mitigates exist in the first place.
> Surely some of their customers have competent accountants maintaining the business's books. This unasked-for effort will make their job harder.
Uh, why? It's trivial to present information tracked as positive debits and negative credits in two positive columns; keeping the internal architecture of the database this way should be irrelevant to the end user, it's just avoiding using a hack designed to optimize the experience of people doing a manual process with medieval European technology and attitudes towards negative numbers in an automated backend where none of the problems it mitigates exist in the first place.