In theory, fly-fishing is a simple sport: Pick a body of water, choose a fly-fishing rod, select your “fly” (or bait), tie a secure knot, cast your line and, hopefully, land a fish on the other end.

We’re all multitasking. Probably way too much. Often at the wrong times. Too many of us, more than we will admit, text while we drive. We check our Twitter feed and Facebook activity while we eat ...