I think you are correct in saying that flushes can be hard on the liver. My suspicion is that they are also hard on the adrenals, so I space them out. One month in between is my minimum, usually more like 6 -8 weeks. I know some people do them every 2 weeks, but I think it puts your body through alot.
Same thing with chelation. I know some people do it every weekend, but my minimum is again, one weekend per month. I would rather go slow and steady and see gradual improvements than have a sudden crash.
They both do help though, and while uncomfortable, are not nearly as bad as people fear. I'm sorry I didn't do them both earlier because I was afraid.