Simon Martin and Joel Skidmore have recently published in The PARI Journal and posted on Mesoweb their intriguing new analysis of the age-old correlation question — that is, how we best reconcile the ancient Maya and Gregorian calendars. They offer the possibility that the standard Goodman-Martinez-Thompson (GMT) family of solutions so widely accepted by nearly all Mayanists for many decades may be off by up to a few days.