Can half and half be substituted for heavy cream in this recipe?

I would actually not recommend it. You need the greater amount of fat from the cream to compensate for the utter lack of butter in the dough. I've made variations on these about 6 or 7 times since it was posted. I haven't always had the full amount of cream. Sometimes I've substituted using part half and half, or a rich buttermilk I sometimes have, to replace some of the cream. In my experience, you need at least 3/4 cup of a full or nearly full fat ingredient. ;o)

I'd think it should be fine, but Merrill might know best.