graeme_p - 4:16 am on Sep 26, 2011 (gmt 0)
On my planet a competent editor will not tolerate needless complexity.
Needlessly is the key word. Sometimes long words or sentences are needed. One long word can replace a short phrase. Sometimes it can be easier to read one long sentence that several short ones.
It depends on your audience, and on what you have to say. There are good reasons why,for example, academic papers are hard to read according to tests like this, even if they are well written and easy for their target audience to read (of course some are badly written).
My site is 1% basic and 45% advanced, but was not affected by Panda. My feedback from visitors has consistently been that it is well written and easy to understand.