I don't know how regular the traffic is but, in May, we encountered one day of it out of seven days. It was our shopping day and there was people, taxies, golf carts and policeman everywhere! We found getting around town to be a bit of a hassle and it didn't take long to head south and then north with the golf cart. lol We found out later in the week there were 5 cruise ships in port that day.
Me, I plan to avoid going into town on those days!