The devil is in the detail - An apparently attractive package hides some unpleasant realities that will only become apparent with experience (and when people 'read the fine print'): 'The Chancellor's 2p cut in the basic rate of Income Tax grabbed the headlines, but - as so often with Gordon Brown - the devil is in the detail.'
Put out to pasture - retired. Pasture is green fields. A horse that has finished its working life is (if it's lucky) put out to pasture. The old people ("geriatrics") were pensioned off.