Send unauthentciated SMTP

If we permit unauthenticated SMTP over port 25 on our mail server, can we simply leave the following fields blank in the user setup:
- Username
- Password
How about these fields:
- Auth Type (I presume we'd leave it set to 'Plain')
- Use SSL (I presume we'd leave it set to 'sslOff')
I'll admit I didn't just try it, and I've traced some of the scripts that pass these values along to the plug-in, but rather than master the plug-in I thought I'd ask if it's as simple as this.
Call me lazy
TIA
- Username
- Password
How about these fields:
- Auth Type (I presume we'd leave it set to 'Plain')
- Use SSL (I presume we'd leave it set to 'sslOff')
I'll admit I didn't just try it, and I've traced some of the scripts that pass these values along to the plug-in, but rather than master the plug-in I thought I'd ask if it's as simple as this.
Call me lazy

TIA