Sophos and Local Security Groups

Hey,

I have been looking at the Local Security Groups created by Sophos.

I have read the descriptions and I think I am clear on what each group allows it's members to do. However, I am not entirely sure of what role they play in the overall functionality of the Sophos software itself.

I have been searching for some documentation on exactly how these groups are used and what the difference is between the Domain accounts and the Local accounts, but I have been unsuccessful.

I was wondering if anyone knows of a document that explains them?

I was wondering how they are populated? Are they populated by automatically? I think they are because on almost all our machines the user that uses the PC is in the SophosAdministrators. 

Do these groups play a role in the ability for virus's to be cleaned off the system? Let's say if a "Cleanup" was issued from the SEC, do these groups have to be populated by specific users in order for the "Cleanup" to be successful?

I want to make sure they are being used properly. We are not experiencing any issues, but I want to make sure I'm understanding their functionality and role correctly!

Thank you,