"and did I mention it was an enjoyable traffic free drive"
We spent 3 weeks in Maho Dec/Jan and only once were we held up in traffic on Union Rd and that was because of a car accident. Other than the usual stop and go traffic in Simpson Bay and that's because of people trying to find a parking spot and of course driving through Marigot is always bad.
When there are lots of ships in the traffic is usually bad on the Dutch side because of the amount of tour buses on the road. One pool day on the deck of La Terrasse we counted 10 double decker buses that parked across the road from Maho Market to give their passengers their 1/2 hour on Maho Beach, traffic was a mess. Not to mention the other buses that drop their passengers off for the day at Maho Beach.
We use the Tortuga Cam for checking out the volume of traffic. When the cam follows a plane down to the end of the runway (Lagoon end) you can see if the traffic is parked or moving into Simpson Bay and also you can see if the traffic is moving towards the Causeway.