It just occurred to me why the SK chose the North side of Ocean Parkway (Westbound) near Cedar Beach to dump the bodies. When I was a teenager, Ocean Parkway was the place to go if you wanted to speed and not usually get caught.
It is a perfect straightaway.
In Suffolk county, the speed limit is 55 mph while in Nassau County, the speed limit is only 40 mph. It is my thinking that the SK chose the location near Cedar Beach because there was less of a chance of getting caught here by LE. Ocean Parkway is a State highway. The NYS Troopers are responsible for patrolling the roads. On occasion, the NYS Parks Police will also lend a hand.
At the very East end of this barrier island is Captree State park as well as the ramp to the bridge that leads to Robert Moses State park less than a mile south.
At the far West end of Ocean Parkway lies Jones Beach State Park.
Cedar/Gilgo, like Oak beach are Town of Babylon beaches. They are situated almost halfway between the State Parks.
Do you get where I'm going with this?
State Troopers and State Park Police would tend to gravitate towards the State Parks where they would have access to facilities (rest rooms, snack bars, etc...). The millions of visitors to these parks creates a ton of work for them to do too (car accidents, vandalism, fights, etc...). The section of Ocean Parkway chosen by the SK.... well there isn't much there. The nearest facilities are the Cedar Beach Marina (town permit required) as well as the actual town beaches themselves (town permits also required).
Also, I think the SK was backing his vehicle up behind an outgrowth of brush high enough that a driver speeding by in a car probably wouldn't notice. The spots he picked were far enough away from the entrance ramp to the highway that by that point in the road, most people would indeed be moving pretty fast. (See this-
http://www.newsday.com/long-island/nassau/state-police-ticket-138-drivers-on-ocean-parkway-1.1372992)
This is why I am totally convinced that the much older remains found in Nassau of the man and the child ARE NOT the work of this SK. They were both found in an extremely busy section of Ocean Parkway where the speed limit is slower and the police presence is tremendous.