The USCIS has issued policy guidance to define Extreme Hardship as it should be applied by immigration officers adjudicating waivers and other applications which require such a showing.
This is a welcome development as the standards and results that have occurred have varied widely throughout the US immigration system. Now there is some further clarity and a guideline to follow in making the strongest case for such a situation. In particular, it appears that there is a formal recognition of certain arguments that have been made by practioners such as IBLF over the years, such as the hardship that results either from deportation of a spouse by the spouse's absence, or the necessity of the remaining spouse to relocate by reason of the deportation. This appears to recognize that separation of spouses is NOT a normal circumstance in normal inadmissibililty, but takes into consideration that consequences of deportation should properly include the relocation of the spouse.
This policy guidance is located at https://www.uscis.gov/policymanual/HTML/PolicyManual-Volume9-PartB.html .