I've been drinking kava on and off for 13 years, and I'm still learning. I still make rookie mistakes on a regular basis, like overdoing a heavy variety and having a bad experience. I'll start too early and end up wasting a possible productive afternoon. I won't drink enough water or skip dinner, and end up with headaches. I'll eat dinner way too late and wake up with reflux and a sour stomach.
All of these issues, I've seriously just figured out over the last year or so. For me, after kneading, I'm left with about a golf ball sized amount in the nylon, and about 20 oz of grog, which I drink in 3-4 go's, over an hour and a half.
I guess what I'm trying to say is:
Some people sip, most people chug.
Some make it thin, others potent.
Some take it easy, others push the envelope.
Some people's stomachs are sensitive, others toss and wash.
Everyone has a preference on how they Prepare and consume, and I am almost certain that even the most seasoned veterans still regularly screw up and have less than pleasant experiences.