kockatea, page-28

Good point bulk.
Given that we don't know where the fracc fluid went to strike the Oil in the first place.
The fracc fluid will take the path of least resistance and may have gone into a clay infused zone, that added to a waxy crude may well be the problem.
Requires an engineering solution once the problem can be identified.
They (NWE) will need to revisit the cores from different zones to help with the diagnosis.IMHO.