I do not have a specific example, but hopfully someone can provide one.
However review the medical standard
Since a waiver is requested, I assume that DS does not meet the medical standard. The letter, at a minimum, should address what is identified in standard and describe how/why what he does not meet will not have an impact on his military career. Below are the points from the medical standard for ADHD:
Attention Deficit Hyperactivity Disorder (ADHD) (314) UNLESS the following criteria are met:
(1) The applicant has not required an Individualized Education Program or work accommodations since the age of 14.
(2) There is no history of comorbid mental disorders.
(3) The applicant has never taken more than a single daily dosage of medication or has not been prescribed medication for this condition for more than 24 cumulative months after the age of 14.
(4) During periods off of medication after the age of 14, the applicant has been able to maintain at least a 2.0 grade point average without accommodations.
(5) Documentation from the applicant’s prescribing provider that continued medication is not required for acceptable occupational or work performance.
(6) Applicant is required to enter service and pass Service-specific training periods with no prescribed medication for ADHD.