I've done some reading on flushing and have come up with some interesting conclusions.

Is flushing really necessary if you're using liquid organic fertilizers?

Is depriving your plant of food the final two weeks of development wise? Wouldn't it stress the plant?

If you're growing in the ground how would you flush without over watering?

I have a few plants left in three different stages of flowering. I've decided to feed up until harvest but only 50% of the recommended dosage, I will give just water the final two days though. One plant is consuming about a gallon of water each day and is only a week or so away from finishing, I have serious doubts there is a nute build up in this soil with that amount of water consumption.

FWIW I tried this and it definitely worked. Two plants I watered with lemon oil extract a few hours before harvesting and let me tell you there is a significant lemon smell and flavor to the bud. As soon as I could smell the lemon aroma coming from the plant I pulled it.