Simple as stated. If you believe that what you forgot to write pertaining to an MHS is a “truly exceptional talent you wish to share” with college admission officers, then you do it as directed. Think back: Is MHS really worth sharing?
Honestly, nothing will go against or affect your evaluation because…
- they deal with these additional info request every day, so they do not expect something exceptional or superb about additional information.
- they won’t remember or care later during evaluation that you asked about it (if you are really concerned about whether they will remember that you requested to add something not that talented).
- they do not put much thoughts into stuff unless it really stands out, and I doubt peer tutoring really stands out.