The way I was told, sharpen one side at the chosen angle until you can feel a burr with your finger that runs along the entire edge of the side opposite to the one you've been sharpening. Then turn the knife over and repeat 'til you feel the burr on the other side. Then remove the burr by drawing the blade sideways several times at the same angle the full length of the knife.

I used to over sharpen. I found out I was creating a "wire edge": a super sharp edge that unfortunately is so weak that it folds over and breaks off when any stress is applied to it. That's why my super sharp knives would get dull if you even looked at them. That sounds similar to what you are describing and it's something I now try to avoid. I wonder if a wire edge would be good for a filet knife though?

Regards, Vince