I often use TextEdit to quickly paste text and do some quick editing. The 'Open' dialog had always bugged me. I never saved TextEdit documents in iCloud, so it just added an extra step when opening the app. My friend @jck told me how to stop it.
- Go to System Preferences
- Go to iCloud
- Disable Documents and Data (this will be system wide)
TextEdit will now open to a blank document. This works on Mountain Lion and Mavericks (a little birdie told me that you have app by app control over this in Mavericks).