I harvested couple of plants with fem seeds already with this sts technique. This article posted above is just for a start. Some MJ plants will produce male flowers with 1:9 ratio(as stated in howto). But i've seen numerous cases, including my own where i had to up the ratio. I found 1:2, 1:4 ratios working fine for me. You could even go with 1:1. I did not see yellowing mentioned in the howto. Was spraying every other day. It takes about 2-4 weeks for male flowers to fully develop.
I even revegged one fem>male plant and then it was forming fem flowers again.
Hope that helps, cheers