steerpikegg - 11:03 am on Apr 14, 2011 (gmt 0)
Here is another example taken from the Panda discussion thread:
Last year someone had a penalty reversed because an iframe generated a false positive for their "too much white space" metric. It was documented on Google's own forum, and JohnMu got involved to place a flag on the site, in case it ever triggered that penalty again.
Again, Google are dictating exactly what you can and can't do with page design.