Barry Sanders
Barry>>>
Na, he saw Jesse was a weak link. He was a junkie.Gus had no plans to replace Walt until Walt killed his goons.
After that he approached Gale and asked him how soon he could replace Walt.
That was at the end of season 3.
Prior to that Gus had no beef with Walt, and didn't really care if his assistant was Gale or Jesse.
Fred.
He probably figure Gale would learn from Walt and Walt would checkout from the cancer