Questions on Pyramids and Linkwheels

Okay, so I'm well aware that "over-optimization" can penalize your site. However, what I want to know is, how many back-links do pyramids/linkwheels count for? For example, let's say a pyramid has 50 high pr web 2.0 sites that point to your money site. Then, 5,000+ back-links point to your web 2.0 sites. Does this pyramid count has just 50 back-links for your moneysite or does it count for the full 5,050+? If I used like 5 pyramid packages or something, then would I be around 250+ links or 25,000+ and thus be "over-optimized"? Also, how many back-links for a BRAND NEW site count as "over-optimized"? I'm aware that no exact number can be given since it depends on a lot of factors, however, what do you guys recommend out of experience?

Also, on a side-note, why do people host on multiple accounts for the IPs? What is the amount of websites I should have linked to a single account then?

Thanks for the help in advance :D