You will read and hear lot's of different opinions,
and possibly start an argument, but it's really neither here nor there.
I haven't used FP as I thought these products were mainly for hydro.
Using Only water for the last 2 weeks is good to get rid of any nutes still in the plants system.
Several days of darkness before harvest is said to bring out the full flavour and aroma in the buds.
Some people say to stop watering so the plants dry quicker.
Does any of this make a huge difference??, doubtful.
Sorry if I have confused you more, but it's best to experiment and find what suits you.