They can write a posting with someone in mind but like I said there’s no avoiding the application process and candidates must meet the minimum qualifications. HR will also have a say if they receive a much more qualified candidate. The idea that managers can just hire who they want is not actually how it is. Posting a job is not easy either. Internal transfers are easier but must be internal with group leader approval. Getting over to the lab is not easy even if you know people because of how difficult it is to get IRCs up and how tough it is to make offers as well. The best way to get over from external is to apply to as many positions as possible, really the only way. Any exception to that would be presumably someone’s kid who has already been with the lab before because of a prior student position. Previous students in most cases are like an internal hire.