Final answer:
The INCORRECT statement regarding letters to unsophisticated clients is that a practitioner should always attach a file memo for more detailed information, as this might not be appropriate for such clients.
Step-by-step explanation:
The statement, "A practitioner should always attach a file memo to give the client more detailed information," is INCORRECT regarding letters to unsophisticated clients. It is important to communicate in a manner that is understandable and does not overwhelm the client with unnecessary detail. While it is beneficial to be transparent and provide information that supports your guidance, attaching a detailed file memo might not always be appropriate, especially for unsophisticated clients who might find it confusing or overwhelming.
Instead, a practitioner should tailor the communication to the client's level of understanding. This includes avoiding legal jargon, being succinct, and clearly explaining any necessary action without excessive reliance on detailed legal rationale or citations to controlling authority unless they are particularly helpful to the client's understanding or specifically requested.