Your comments

Giving this thing a second thought, there is yet another way to do it: Automator!

Just created this workflow:

And there's also a workaround for the "save as.."-problem:

In case you didn't know: You can save the workflow as an .app-file (so you can create a shortcut to it as I wrote before).
Well - isn't it possible to subclass the NSDocumentController and override the default behavior?

Anyhow one can disable Textastic in "System Preferences...|iCloud|Documents & Data (Options...)". This will open Textastic with an empty document.

For me switching off iCloud is not desirable so I found this workaround:
- Create a shell-script somewhere with this single line: "open -t `mktemp -t txt`"
- Create a keyboard-shortcut (like I recommended here:

(will require to configure Textastic as the default text editor)

It's not a perfect solution, since with stupid auto-save you cannot "save as..." (you have to duplicate first, or you will save the temporary file). Anyhow most of the time I just need a place to store / edit some text, so it's okay for me.

It would be soooo good if one could switch of auto-save (*wink-wink*, Mr. Blach). Not only for the workaround. I do not like auto-save for text-files at all...