I have experimented with 12/12 from seed a few times. For me (with seeds, not clones) it would take atleast 3 weeks before it started to flower anyway. Is that the same for you with clones? I decided after the experiments that I might as well have them in veg for those 3 weeks to get as much growth during that time as I could. I actually do 4 weeks because if I am going to veg anyway, might as well get a topping in before throwing them into 12/12.I run a "no veg" garden. I take cuts from a momma, after a week or so I transplant into flowering pots when rooted, then harden off under flower lights at 24 hrs for a few days. Once they harden off I flip to 12/12. Virtually no veg time and a crop every 8 wks. This allows me to run a lot of different strains in shorter periods of time. If I find something I like, I keep the momma. If its not worth keeping, I cull the momma after I am able to test out the smoke.