Binding keys will allow you to change the keys and key combinations that tmux will recognize for any command. This also allows us to create new key combinations for existing commands or change the key binding for any existing keys used by tmux. It even lets you assign new key bindings to any command we can dream about.
The commands to which we can bind keys can even prompt for user input. There is no constraint on uniqueness, so we could bind multiple keys to issue the same command or bind no keys for a particular command.
What this all means is that while there is not an existing key combination available to reload the tmux source file, we can make up our own key combination and assign it to the rather lengthy