Early sexing method

What does anybody think of this? I came across it in a grow guide from Weedfarmer.com ive never heard of it before, anyone out there have experoence wit it?




EARLY SEXING
It's possible to tell the sex of a plant early, and thus move male plants out of the main growing area sooner by covering a plant's lower branch for 12 hours a day while it's in a constant light
vegetative state. Use a black paper bag or equivalent to allow for air flow while keeping out light. Be sure to set up a regular cycle for these covered branches. If light is allowed to reach
them during the dark period, they may not indicate early at all.
Use a magnifying glass to look at the early flowers sex type. A male plant will have a small club (playing card) looking preflower with a small stem under it. A female flower is usually a
single or double pistil, white and wispy, emerging from an immature calyx.
Some people like to pre-force plants when they are 8" tall, in order to weed out the males.
When growing outdoors, many growers do not wish to devote time, space or energy to male
plants. Just put the plants on a 12 hours light cycle for 2 weeks, separate the females from the
males, then revert the light cycle back to 18-24 hours to continue vegatative growth for the
females. Keep in mind, this is a time consuming process and can put the plants back 2 weeks
in growth. Don't pre-force plants unless you have lots of time. Just cover one branch per plant
with black paper (light tight, breaths air) 12 hours every day under constant light to force pre-flowers
and differentiate early

sounds like it could work

Not practical at all.
Undue stress issues aside, maintaining a regular photoperiod is nigh on impossible unless you have an alarm clock telling you to go switch your paper bag. Plus the size of plant that you need to have these large low branches- a plant that big is mature anyway and should be preflowering, or at the very least, you should already have taken clones off it to sex in the traditional manner.
Cloning for sex is the right way to determine sex without flowering your whole plant.

Its backwards productive, it says it sets your grow back 2 weeks. While the whole time you could have just waited those 2 weeks to find out the sex naturally.

The best way I have found out is to
1 wait till you have 4 branches
2 start clones off them mark all plants
3 after roots have started switch the space to 12/12
your primary plants have grown for 4 weeks
at first signs of males trash them ,,, note first signs (they are numbered )
4 replace the known males with females in the on you primary system
you will loose some groth with them but will harvest all females
The gain is you can test your females sooner and cull any ,and find out which, its going to be like. (you might be supprised there may be a differance)
Remember to clone the good plants before switching the primary plants to bloom
ADVANTAGE
you get to test the strain, and have all females, clones for the next run.

oldsanclem's method is also called 'cloning for sex' and is the way that experienced and efficient growers operate.

You can also do this:
Cut clones from seed plants
When the clones root, put the CLONES in flower in small pots.
When the males show, throw away all the male clones AND the donor plant they came off.
You are now left with all females.
You can take some more clones now, again numbering them according to which seed plant they came from.
At harvest time, determine which of the clones performed the best in terms of yield and quality.
Put all the OTHER donor plants into flower except for the really nice one, and all the clones you just took. This is your second crop, and will be the last one where you see significant variation.
Save the nicest one to be your permanent mother, and take another round of cuttings from her for your third and subsequent crops.