You can learn a lot of stuff by watching outright sweeps. Like this one
Here, I display the advantages of a double sacrifice. I think the worst move my opponent made was on the first turn when he straight up went to Outrage. This allowed me to Intimidate it, while getting the free switch back to Deoxys for the Reflect and Stealth Rock. I gained even more momentum when he KOed Deoxys, which gave me time to send out Scrafty and set up a couple of Dragon Dances. He could have stopped me by just using Earthquake during my second Dragon Dance, softening me up for Dragonite's ExtremeSpeed. He chose instead to Taunt and pay the price.