Surely it's not unheard of, but as a former 'consultant' I would always be amazed that the client hadn't documented their workflow by the time we showed up. We'

Surely it's not unheard of, but as a former 'consultant' I would always be amazed that the client hadn't documented their workflow by the time we showed up. We'd usually have a team of BA's work with the client for a few months before code was written, all because the management didn't know how their business ran. Reading between the lines here, it seems that perhaps the IRS is in a similar situation, and the only canonical source of truth for how things work is encoded in the assembler source code.