Welcome (I would insert the smiley but WTH is wrong with them right now, did I miss something?)
http://www.ballpython.ca/what_get/recessive.html
The second row explains how you get 66% hets in a clutch when breeding a het x het. You actually only have 50% hets but since you cannot physically distinguish them from the normals, all of the ones appearing normal (whether or not they have the recessive gene) are considered 66% hets.