I use the opposite of your flowering cycle. I use 13/11. I read that 12 or 13 hours produces more potency than 11 or less. Also yield is considerably reduced with 11. I saw one forum post somewhere in which a guy tested his weed grown with I think 10 hours and it was about 2/3 the potency of his 12 hour weed. Might have been 11 but I think it was 10. 13 is working well for me so far. Just started using it a few weeks ago though so can't really say for sure what the results are yet. Just seem to be growing somewhat faster.