My guess is, being that Chaikel is US Gold, their miles are (at least sometimes) worth more to him then CO, hence the "'some' consider it more valuable".
Even as Gold I don't see why they would be more valuable.
-They charge a ticket processing fee up to $50.
-They charge $150 for date/routing changes that are free on CO.
-They don't allow any changes on *A tickets after travel starts.
-They don't have partners like Virgin Upper Class like CO does.
-They don't have one-way awards like CO does.
-They don't have an expedite workaround like CO does.
-They don't have 20K short-haul awards like CO does.
-Their agents are completely clueless and it takes hours to book some partner awards.
What have I missed?