The yeild increases are strain dependent, but to be more detailed. The OG's had 25% more yeild than before under "standard" 12/12. For plants with higher yeilds it could be a waste of time with calculating days and digital timers etc. Remember you can make no mistakes!!! I woke up with two alarms for weeks to accomplish this, now there are timers out to ease the transition. Try it on one plant to see if it meets your needs.