Having done dozens of flushes I can say how flexible the flush protocol is. I'm weary of Clark's admonitions that if you don't do this or that it won't work. That's long been disproven. I started with her's and kept making changes and STILL experiment. But the minimum bottom line is fat free eating during the day, ES in the evening to relax and open the ducts and 1/2 cup Oil to cause the contraction process. (Type and ingredient combination are open to experiment). Check my history, check my blogs - I have a lot out there on my flushing experiences.
Check Telman's posts for technical explanations.
In summary for me - Can't avoid the ES (yuck), Sunflower Oil/OJ/eggyolks, Next day - SWF (Salt-Water-Flush) x 2. In between, lot's and lot's of water.