Buddies and Using Codes

I am confused as to whether Buddies need to use the Passcode and would appreciate some guidance.

 

I have installed the retail version of NMS with the NAT plug-in for my Verizon Motorola Droid2 Global.

 

SMS Anti-Theft Settings have all of the following with green check marks: Remote Scream; Remote Locate; Remote Lock; Remote Wipe; SIM Card Lock; Security Wipe.

 

My wife's cell phone is listed as one of the three Buddies.

 

I had my wife send a text message with only the "scream" command that was received on my cell as a text message but no response. When I had her add the Passcode it worked.  

 

Is there ever a time that the Passcode is not required when a Buddy sends a text message to my device?

 

Please correct what my notes reflect:

 

To lock: lock (passcode)

To Scream: scream (passcode)

To wipe all data on your phone send: wipe (passcode)

To locate: locate (passcode)

To unlock your phone: (passcode) [note that passcode may not be required and only word “unlock” or simply passcode]

 

From a long time ago using the original free version, I made the following note:

Buddies: Remember the "unlock buddy" code is "unlock" and their phone number not your phone number.

 

Thanks