You also say:
"However, if we had the "length of life since diagnosis" for patients who took orthodox treatments, and compared this number to a similar group of patients who had refused treatments, we could quickly tell whether orthodox treatments were any good. But none of this data is kept, it must be dug out."
I have never seen any statistics on the effects of alternative treatments for cancer, either length of life, 1-year, 5-year or 10-year survival. You say yourself that no data are kept. On what basis then can you make claims like the ones in your comment just now?
You can hardly blame conventional medicine for not keeping data on alternative treatments. That should be done by the altmeds themselves. Apparently they just can't be bothered. Very disappointing.