tedster - 5:23 am on Sep 26, 2012 (gmt 0)
Well, that's a whole other discussion. But if your web host doesn't actually serve your pages, Google may take it out of the index until they can confirm that your pages are available again. Although they certainly do mess up, they prefer not to return search results that don't resolve.
Now about the "whole other discussion", even a one man operation can comply with many/most of those recommendations. I'll bet there is some other cause.
You said "penalize". Does that mean you get no Google traffic, or you lost most of your Google traffic, or you lost some of your best rankings? Also, did it happen on just one date?