Originally Posted by StayingHomeIsBetter

I learned that the hard way on a D1 flight back from Europe.

I recognize that a fully reclining seat is not the only alleged benefit to D1, but with D1 requiring 4X the miles vs main cabin, (example: PHL to CDG, 442,000 miles vs 106,000 miles) a loss of recline ought to yield a hefty mileage reimbursement.