Gentlemen:
Not getting into the discussion re. left/right/etc. laid cables, but lines (shrouds to be exact) were SERVED with small stuff to prevent chaffing from the contact with sails. The leading shroud on each set of lines was covered with a canvas wrap and then small stuff was applied (served) over the canvas. Once this had been completed, the resulting wrapped cable was then coated with tar to waterproof it and provide an extra layer of protection. Back in the early 2000s (doesn't THAT sound quaint???

) I developed a serving machine to do just that for making served lines for my 1:48 U. S. Sloop of War PEACOCK -

- 2nd Version Serving Machine
The serving small stuff was wrapped either left hand twist or right hand twist depending on the side of the ship that was being rigged. I believe back then I was using Bluejacket black cotton line and a thin dia. cotton line for the small stuff. I didn't see the need to actually wrap the inner cable with "canvas", but simply coated the completed served line with flat black paint.
About the best photo I have of this completed "served" line is this:
If you notice the leading shroud is somewhat thicker than the ones behind, thus illustrating the aforementioned process.
Torpedo the dams!!! Full Speed to the Head!!!
Hank