For me less has always been better. I only have one ad at the top of every page. Every couple of years or so, I experiment by adding a second ad block embedded in the content further down the page and by ctr drops. Sometimes after adding the second ad block I'll get a jump in revenue for a short period but shortly thereafter earnings drop back down to what they were with just the one ad at the top. No point in running two ad blocks if the earnings are the same with just one.

Has anyone ever removed an AdSense ad from pages and had an increase in CTR

Yes.

I also saw an increase in overall performance by removing adsense completely from pages that did not perform well. Site stats overall went up.

This is good news. I'm going to give it a try. Thanks for sharing.