I also carry 4 rods, and I have to admit to having 5 on board on occasion. Generally I take a drift rod, another rod with a lighter or heaver weight for faster/slower water, a spinner rod, a float rod, and a plug/plainer rod.
I let the water conditions and situation dictate which rod I use. On several trips last year, I had a "go" on each rod. In addition, I've had a take on the drift gear and been unable to get another strike until I tried the bobber or rowed back up and run plugs down the slot. Some days one system really outfishes the others---besides it keeps the rod & reel manufactures in business. It's also a good response when the wife says, "Dear, why do you need another fishing rod?"