I'm curious how long you did the three minutes per day before doubling to six, and likewise for the time before doubling to twelve.
About every three months I've doubled it. It got to the point where the 3 minutes of time started instantaneously passing and then the same thing happened with 6 and now its starting to happen with 12. A very weird / cool feeling that really builds over time
I find its best to do 12 minutes in the morning, right when I wake up. No food yet or anything; just leave the bedroom, head to the corner of the room, hit my timer and go. 12 minutes is my happy medium, but it took some time to get there; I started at 3 (can't argue with 3 minutes) then doubled it to 6, then doubled it to 12. On the weekends I do 24, and often times more. But the key was building up from that initial 3 minute daily commitment.
I know everyone hears this all the time, but Meditation is the greatest thing. Hard to explain unless you do it every day, but it has such a wonderful transformative power. Its really helped improve my code, too.