Exactly what I was thinking. Gamefreak must have noticed all the Explosion-spamming at official tournaments all over the world because they use the Double Battle format, which is almost completely centralized around Explosion. Remember how when triple battles were first revealed, most people scoffed, saying that Explosion would just be more prevalent than ever? Gamefreak obviously took the opportunity to prevent that, and make it a more balanced move in those formats. Its horrible nerf in Singles is just a nasty side-effect.GF probably had more than one eye on triple battles and the effect of explosion there and with in mind, i can't say i blame them.
Seems a lot of our Pokemon will need adjustments to accommodate this huge change. I guess Damp will now join the ranks of abilities like Keen Eye....