[StellarScience]

Ignoring the git commit message strawman (those can include "what/why the change", not "what/why the code") and the Uncle Bob strawman, the final code block looks fine. But notice:

  // translate will replace all instances; only need to run it once

This is a "why".

  // Replace all symbols

This is a "what". It's better conveyed by improving the function name rather than by a comment:

  String replaceAllSymbols() {

Ultimately this article buttresses conventional wisdom about comments.