It's all a little freaky if you think about it: even in evidence-based medicine, a whole lot of it is people making qualitative determinations and squishy adjustments to treatment, and undoubtedly getting it wrong a whole lot.
Then again, the stuff shows benefits in trial, and presumably we get most practitioners trained up and doing the thing that's the standard of care well enough...
There might be the perfect amount of paracetamol to take to treat your light headache.
But in practice people just take two 500mg tablets and call it a day. Works well enough most of the time, even though it might be 'wrong' in some platonic sense of the word. (Eg you might have been helped enough with a slightly lower dose. Or perhaps 1250mg would have been better and suppressed slightly more of the pain. Who knows?)
There are plenty of doctors that rather die than treat their cancer. There was even a "recent" HN story about it. The motivation is that for a nasty one, the treatment is often worse than the disease, and they rather spend their wealth and to easy their pain and enjoy their last months of living rather than going through a very hard process that might not work, might leave them in an not that good state.
