i personally use a 4" piece of telephone wire wrapped very tightly around the trolling wire. i start by placing the telephone wires middle 90 degrees from the trolling wire and wrap each half in opposing directions and finish by using a pair of pliers to smooth the end of the tele wire around the trolling wire. it never slips on me and i vary the depth of the wire for varying conditions. try not to jig the exact same area repeatedly to avoid weakening the line. the splicing method sounds good,especially if you want to save a 1/2 used spool of line.
by the way i was looking at the boaters world catalog and found they offer 3 types of wire line rods for under $100.00
also the fisherman magazine has videos for sale that show how to troll wire line,al lorenzetti is the producer and you would find it very informative. (great stocking stuffer

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