I like to tie my droppers off the bend of the hook. I don't seem to get to many tangles unless I do something wrong in the timing of my cast. If you are casting a double rig and you are getting tangled a lot, chances are it could be your casting. In that case I would work on casting with one fly. As far as the dropper bead goes its another thing to add to the equation. The more things you add the more complicated things get. Keep it simple.
Matt
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