I second rcantor's comments. I start in moss also and cup the cuttings once there are root initials, I place the cups in humidity domes for the first 1-2 weeks only, at 75 deg F. (to aid in root growth). After the 2 weeks they are placed in a south facing window where they are acclimated to the room. I believe that your situation is the optimal rooting condition, roots before leaves. A large healthy root mass will be able to support any leaves that the cuttings can produce.