Yes, as a matter of fact I do fertigate 2 hours before I harvest at the end of the day. I add molasses once a week the last two weeks prior to harvest. The plants stop sending exudates to the roots to encourage additional nutrient production in the last two weeks in order to send ALL of the energy the plant produces to the buds. By feeding the microbes in the root system some carbohydrates they remain in high production providing all the nutrients the plant can use to fatten the buds.
The theory from Harley Smith is that at the end of the day the plant has a full store of energy and the plant begins drying better in a full energy state. It is a proven scientific fact that flushing removes absolutely no nutrients from the plant - period. Tissue samples remain identical from plants flushed vs not flushed.
That said there may be an unquantifiable change in plants that are flushed. This possibility exists because so many peeps believe there is a difference. I do not.