Coulthard said no to being Ferrari no.2
Weighing in on the teammate histrionics at his former team Red Bull, the Scot said he believes the Milton Keynes based outfit treats its drivers as "an equal partnership".
He said the other option is "the Ferrari/Schumacher route, with one driver openly backed over the other".
"I once turned down the chance of a move to Ferrari as I would not accept being a signed-up number two to Michael," Coulthard, 39, revealed in his latest column for the Daily Telegraph.
He acknowledged that the Schumacher method is "the most effective" in terms of winning championships, "but morally dubious".
"The second (route) is the fairer system but incredibly volatile and difficult to put into practice," added Coulthard.
Having driven for Red Bull until the end of 2008, including two seasons as Mark Webber's teammate, Coulthard said he believes the team when it says Sebastian Vettel is not being favored.
He is therefore not sure if Australian Webber is doing the right thing by being openly critical in the wake of the front wing saga at Silverstone.
"Mark clearly feels he can gain more leverage by going public and trying to shame the team whenever he feels hard done by," said Coulthard.
"It is a risky strategy," he added. "If it goes wrong, the relationship with the team could sour irreparably.
"If it comes off, he could consolidate his position, attract public sympathy and be remembered as a steely champion who battled against the odds to win his title."