For graft injury, it doesn't seem to matter which cultivar was grafted but rather, how late a graft grew into the Fall. Pecan shoots that don't harden off before a hard freeze seem to suffer the greatest amount of shoot dieback.
Pecan cultivars that over-produce and have some southern blood are the most prone to suffering winter dieback. Shoshoni, Chickasaw, and Mohawk are cultivars we no longer grow because of over- production and subsequent cold injury. Last year, we made sure to summer shake our Pawnee and Lakota trees to prevent over-cropping and limit the possibility of winter injury.
Thankfully, we have finished harvesting the 2017 crop and we are now cleaning the last few super sacks our pecans in a heated barn.