[Mithalwen]

Gandalf acknowledges Saruman's lore, power and seniority but comments that he has grown proud and disikes interference in his sphere. Gandalf says that Bilbo's behaviour didn't tally with Saruman's assurances. Then the ring is shown to be the One which proves Saruman wrong and it is in that context that Gandalf speaks of an earlier time when he still trusted Saruman.

Is having doubts about someone being right who is then shown to be wrong on that matter disrespectful? He doesn't express himself disrespectfully , but if Saruman is the sort of leader who is still right when he is wrong then Gandalf could be described as disrespectful but I think it is a stretch.