My experiences with molasses have been:
For outside grows I start at two weeks growth, mixing two Tsp/Gal as a watering agent through week four. (I don't transplant outside until week four) I then switch to one Tbs/gal weekly for the remainder of growth between watering. The last two weeks (three weeks for a kush) before harvest, I pump up the molasses anywhere from 2 to 4 Tbs/Gal depending on the simple appearance of the individual plants. We've noticed that this kind of acts like 'carb-loading', and makes a noticeable difference, increasing bud size at a noticeable rate.

For indoor grows, we simply half these measurements.

I also use molasses in a folar spray in conjunction with King Neptune's seaweed/fish products, adding one tsp. molasses. Once every two weeks.

And before you ask, yes, we have done controlled tests with inside grows. Molasses works. It's been a bit more difficult to test outside with the many variables involved concerning plant placement, soil, and light. I am however a true believer.

As a new member to this forum, I looked for interesting and helpful posts of others, and found an older one by 3LB concerning the magic of molasses. They confirmed our findings, and more....Again, this is just my experience. B