Question about shortcuts / aliases
 

If I am in my context view and I drag one action into another action, a curvy black alias arrow shows up as my mouse pointer and when I drop the action, it creates an underlined, blue colored link to the action that I was dropping.

Does anyone know what the purpose of this feature is?

You just created a link between the two actions. This is really handy when you have actions or projects that are in some way associated. Clicking the link will open the corresponding item.

I typically create links by right-clicking an item in Planning Mode and selecting "Copy As Link". This gives me a URI to the item that I can then paste into the comment field of some other project or action or even into some other app (e.g. TextEdit, Yojimbo, BBEdit, etc.).