This has come up a few times ("where does it say do X if decision has been communicated to the applicant") and I knew it was out there but had to find it. It is an extrapolation of the definition of making a decision re when an inquiry or prequalification becomes an application.

"1002.2(f)(3)
When an inquiry or prequalification request becomes an application. A creditor is encouraged to provide consumers with information about loan terms. However, if in giving information to the consumer the creditor also evaluates information about the consumer, decides to decline the request, and communicates this to the consumer, the creditor has treated the inquiry or prequalification request as an application and must then comply with the notification requirements under §1002.9. Whether the inquiry or prequalification request becomes an application depends on how the creditor responds to the consumer, not on what the consumer says or asks. (See comment 9–5 for further discussion of prequalification requests; see comment 2(f)–5 for a discussion of preapproval requests.)"

This has been used legally to say that a decision must be communicated to be effective.