It is fine putting a seedling or clone under a HID light, but you will be wasting a lot of energy doing so. You will also need to hang the light fairly high to prevent photodamage. As young plants cannot photosynthesis at high levels in early stages of their life. Although some strains are more tolerant than others, this is just a result of efficient photoprotection systems. As such doing so slows the whole process down as the plant trys to survive through the stress from light.
If you have a lux meter, shoot for around at least 5000 lux, no more than 20,000. Preferably though, i would just put the girls under some CFLs save some money from the wasted power.