Update on image/text, invalid clicks

Just saw a thread started a few days ago about experimenting
with text/image.

For what it's worth, I thought I would do an update on my
experiment. I changed one large, authority site to text/image
at the start of the month.

The first week, all things were relatively equal to last month.
Then it slowly went south, and I changed them back to text
yesterday. Things started looking up. Now I do admit some
days were off the chart! But overall, the money was less,
due to some days really sucking.

My testing for me is that it was not worth it in the long run.
I test things for at least 2 weeks, that's why I did not change
things back right away.

One thing that I would really like to add as a conclusion of
my experiment, is on invalid clicks.

I had always got a few invalid clicks daily, having a few bucks
taken here or there in the course of time. BUT...it dawned on me
that my invalid clicks and money subtracted increased at least
4 fold.

I can only attribute this to image ads getting brush-clicked or
"accidentally" clicked more than text. The ad space is taken up
completely by a clickable ad, so it makes sense.

I would like to know if anyone else has experienced this or what
you thoughts are.

Paul