Secretly switch the coffee to 75% regular Folgers 25% decaf. Do this for 2 weeks. Then switch it over to 50% regular Folgers 50% decaf for 2 weeks. Then switch it to 25% regular Folgers and 75% decaf for 2 weeks. Then switch it to 100% decaf for a final two weeks.
Then toss in espresso roast and see what happens.