I disagree with the proposed suggestion. There are cases when supervisors or even managers are contractual. In those cases, it would be better to have input from HR as the concerned employee will add value to the organization.
Obviously, there should not be any official record. HR's representatives will conduct the interview, help fix the remuneration, etc., but the entire process should be documented under the contractor's domain. For workers, the contractor will likely be capable of handling the job, but if necessary, HR's representative may intervene.
Regards, S K Bandyopadhyay