yes molasses help your soil`s micro life, with carps, that help the plant ..
beside that it also contains stuff like Ca/Mg Iron, zink, copper and other trace elements the plant need to take up nutrients..
I use it, last 6 week of flowering, a ts. in a gallon of water, fist deluded in a cup of boiling water then added to the water can, every other watering, in between nuts ..
some also report of "sweet" buds, dunno about that tho, just know its cheap and helps the plant with organic micros in flowering and I like to help my plant in flowering ..
about your 8-4-4 "Veg nuts"
I agree, need to stop high Nitrogen in flowering, tho fist two weeks of flowering (the stretch) is where the plant use the most..
so I would for sure continue with it a week or two, I do fist reach max nuts dose in flowering, and I fist start on the molasses and high P/K and other bud product once the stretch is over and last 5 weeks or so, fist two I treat like Veg. so to speak ..
final week I only use clean water and plenty, so Im sure the plant have used up any nuts left in the soil ..
this is what I use in Veg/flowering:
and remember less is more, keep it simple, find a few good product and get use to em, tho different strains also play a role here, some need high nuts and some is really sensitive ..