My site was on the first page of Google 7th position and after i bought a backlink package that added 2,000 backlinks in 7 days it went to the last page.
So anyone who tells you to go crazy on backlinks that Google doesn't mind, does not know what they are talking about.
Now before i bought the package i read several times that you need to build your links slowly. Man, i wish i would have listened. Lesson learned.