That's basically what I did. Yuffie was my healer- she had the Mystile & a Choco Feather on, as well a Speed Plus materia I had maxed out. After hasting, she went pretty often.
Gold Dance & most of their physical attacks would miss her, and I had two characters with elemental/Choco-Mog. Pretty much just beat on the back row guys until they drained their front row counterparts, at which point I switched over to killing them. Haste and regen is important, obviously. Pandora's Box killed Cloud, but only because he wasn't fully healed at the time (sucks, but I had an Omnislash ready and I had to use it).
Now to tackle that boss with the damn auto-Dual....
Edit: not all that hard, surprisingly. Did it first time. Lasered him down throughout the fight, then when it got to the third form, Quad Magic & W-Magic/Gravity, Mimed when possible, with an Omnislash at the end to finish him off. He used L5 Death at one point, which got one character. Again, I kept everyone healed with superspeed Yuffie and White Wind.