Tools that live in history are fine and good ... until they roll out of history.

Mind: I rely on shell history all the time, and I'm noting, admiring, and planning to adopt your commenting hack, it's ingenious.

But once a particular shell hack / one-liner / function has become sufficiently useful and proven, I'll typically add it to a shell function file (~/.bash_functions, sourced from ~/.bash_profile or ~/.bashrc), or my scripts directory (typically ~/.bin/ for personal hacks, /usr/local/bin/ if it's something I'll use from multiple accounts. Also park that under git and back it up / archive it somewhere or several somewheres.