Sherlock spends a lot of time by himself brainstorming and dose not seek help from Dr. Watson through his thinking as much as a cigarettes and drugs. Sherlock used cocaine in The Scandal In Bohemia to help him work around problems as the drug was legal and used in a way of medication
Sherlock Holmes reveals most of his deductions and observations to Dr. Watson after the solution. We can say that Sherlock uses his own intelligence working around clues and ideas and is very independent about them until the end of the story.
Sherlock Holmes is an independent detective in ways. Throughout the story's, we see Sherlock Holmes reveal all his deductions and observations to Dr Watson after the solution. He lets his intelligence figure out his thoughts, ideas and clues and dosen't seek much help from his assistant when brainstorming but, very much needs him through investigations.
Observes glass of milk in the spekled band
Observes vent going from room to room
He solves the king of bohemias case withing 3 days when is other people he hired had not succeded
Solved the red headed league case with not much evidence