i don't post much anymore, but i had to speak on this:
the quoted statement is absolutely false. (besides the fact that your final flush should be water only.) do not listen to this! perfect example of perpetuated misinformation. i'm sure bubba means well, but this is wrong. there will be no sugar left in your bud from using molasses. there will be no residual effect and there will be no harsh taste. harsh tastes come from improper drying and curing, or failing to flush residual nutes, primarily nitrogen, from your bud. molasses is not used as a bud sweetener or flavor enhancer. it is biologically impossible for it to be used for that purpose. molasses is only used because it is a cheap source of carbohydrates. sugar molecules are too large to be taken in by the plant's roots.
quick biology lesson: plants use sunlight and water to convert carbon dioxide from the atmosphere into simple sugars. this is a process called photosynthesis. if a plant could absorb sucrose through it's roots, wouldn't that make photosynthesis pointless?