"But why isn't the load command necessary? How does mIRC know it should load the file since it's completely new?"
The /load command only puts files in your mIRC directory (or any other dir you specify) into the script editor. When you paste code straight into the script editor it's just the same as pasting it into a .ini file and using the /load command. When putting code straight into the script editor, /load is not needed because it's already loaded
And you are of course most welcome