I think I might have read this on some listicle site like Cracked but I can't find the listicle that I actually read it in.
I’m afraid this seems incredibly confusing. From 1777 -1781, Alexander Hamilton was one of Washington’s primary Aid-de-Camps. Are you suggesting that members of the Continental Congress wrote to Hamilton at this time, asked him to write letters to Washington only to immediately pen the replies himself?
Can you please post a source? Possibly a quote from the source that explains what you mean, because by itself, your question is extremely confusing.