Dragon Dance is unfortunately incompatible with Acrobat, its best move by far. Flare Blitz not only gives the nasty recoil, but is unable to never ever break through Alomomola. Alomo will only switch in after you SD first, and +4 Gem Acro just flat out GG's Alomomola. Also, if you can get SR cleared, you can tank a Scald, so you can boost while it switches in, tank a STAB to boost for the second time, and wreck the whole regenerator stall team concept. That alone makes SD significantly more viable than DD.
Also the absurd amount of priority makes DD easy to revenge kill after SR and Flare Blitz recoil.