b3, i always use a large snap swivil on the end of my shock. for simple ease of change is the main reason. before i throw out my anchor i always throw a 6 oz lead first just to make sure the line is loose and i dont nest when i do throw the anchor, saves on anchors breaking off.
as far as the wraps on the spool of shock leader, other then for safty reasons, when you pull a large fish up to the pier and he decides to jet around a piling, you have a better chance of landing him when your trying to hold his head out of the water using 50 rather then 20 lb line.