Colchicine is used for inducing polyploidy in plants which means they mutate and get a doubled up set of chromosomes.
This was based on work by Warmke in the 1940's (if memory serves?)and he reported much larger more vigorous growing plants and also reported higher thc produced but his methodology was found wanting and his findings generally dismissed.
Arjan told me his crew had investigated this but I just don't believe the guy and thats based on my experiences of meeting and talking with him many times.I think the **** Of Cannabis just wanted to sound like he had his thumbs in all pies.
STS or Silver Thiosulphate is a mixture of 2 crystalline chemicals which are applied as a spray one week before a plant goes into flower and on the day it goes into flower.This causes male flowers to break out of the bud sites and pollen is collected and used on an identical clone which will go on to produce selfed S1 femmed seeds.
Some strains when 'reversed' produce seed that hermies badly but others are just fine when grown in a good environment but it's NOT 99% females and 1% hermies,the figure is higher but I've yet personally to get a hermie with femmed seed after doing testers with about 30 plants of 3 different strains.
Also,a plant must breed true for the traits you want expressed in the S1 progeny or all you get is an F2 population of the desired plant along with her sisters,not something Big Buddha it seems is aware of.......snigger!
I've just reversed a Cheese clone in my last journal and will be pollinating selected clones in my next one.You can see in the pic Nana's all over but I've learnt that the seeds on the reversed clone are not to be used,you must pollinate a fresh clone.
Hope this helps.