Can you get the achievements via multi-player system link?

[host advantage]

ok, just tested it not signed into live and it gave me my Have a Nice Day achievement. So, the answer to my question is quite evidently yes.

[host advantage]

Nevermind. Looks like you can. I just got the Pistolero achievement during a system link game. Not sure if it's because I was also logged into Live at the same time though. I'm gonna try for the next one in an offline system link game.

[host advantage]

The ones such as the weapon achievements, like Pistoloro etc, or does it have to actually be online over Live?