Abusing backlink packets on shared ip host

[fresh79]

Here is a question i think i already know the answer to - but want your views on it

The scenario....
shared server with 300+ sites owned by affiliate marketer = 1 ip address
If the marketer decides to outsource linkbuilding using backlink packets, and the link builders build links to www.site1.com & www.site2.com using the same packets - Is this leaving a footprint & is this footprint asking to get google slapped?

Please no obvious answers like "get another server" or "dont put all your eggs in one basket"

I want some insightfull information and experience form others please
TIA