By Andrew Gould The family of John Clayton thanked everyone who sent their condolences and commemorated the NFL insider, who passed away last month at age 67. Clayton’s wife, Pat, and sister, Amy, posted a letter on his Twitter account showing appreciation for those who conveyed grief and honored Clayton over the past few weeks. “We are humbled and awed by this worldwide outpouring from those upon whom he had an impact,” Pat and Amy wrote. “Knowing we share this loss with you gives us comfort as we adjust to a world without ‘The Professor.’ John’s unique brand of knowledge of both the game of …