You only need to provide creds the first time with a persistent connection, from then on you just supply the ref.
It makes no difference if you are only making one transaction, but for two or more you can save 80% of the load on the db, so absolutely it's beneficial.
Logging on, with the associated updating of audit etc, is one of the most expensive transactions you can make so anything to reduce that helps.
Thanks for the information. I was using some other scripts including your Autodomain.vbs as a reference and in the command execution function it looks like it sets the credentials everytime regardless of connection type.
probably, but if the connection type is persistant.use, and you specify a valid ID, then it doesnt do a login. The nice thing about XML is that you can ignore stuff at will