The Dropper-Loop Knot is my preferred knot for joining two lines, and it's easy to tie. First, fasten the end of your leader to your line with a double overhand knot. With that knot at the top, form and tie a regular dropper loop. If you don't know how to tie a dropper loop, follow these simple steps: Keeping the knot at the top, form a loop with the two pieces of line and wrap one around the other eight times. Keep one of the wraps - at the bottom of the loop - open. (A toothpick works well. See photo.) Insert the top of the loop (the overhand knot) through the opening, pull everything tight and trim the knot.
Notice that this knot looks like a blood knot with a small exception: Both tag ends exit the knot on the same side rather than on opposite sides. This makes the knot a little more streamlined.
I've run single-hand charters most of my life, so I've tied this knot millions of times. This is, by far, the quickest line-to-line knot to tie, and it leaves no tag ends that catch in rod guides or snag grass when trolling.
Capt. Ken Roy
Crystal River, Florida