Drooter,
I don’t know if they find it more professional or not but I do know it instills confidence that the job will get done quickly. You have to way the cost/benefit between small jobs and large jobs.
If its a small job, I don’t think it matters at all. BUT, with larger jobs, I find my clients always ask if there will be more employees coming if they only see one worker that day. It just happened today on the plumbing stage. Even though there was only 5 hours of plumbing work to be done that day, it would have made them feel better about our commitment to them if they would have seen more employees.