The only plant I repot dry are cymbidiums. Then I place them in a cool dark place for 2 weeks intil I see new roots growing at the edge of the p-bulbs.
For the other orchids, I soak them for 5 min. before I disturb them in their pots...and the new media is soaked in water overnight and cleaned of its deposits...it is slightly damp when I actually repot...then I wait for a couple of days before I water it.