ha! I can relate to the 'not always good..' part ;)
There is quite a bit of mystery, smoke and mirrors, legend and stories it seems surrounding jetting. It's not that hard.....it's just an unknown in a lot of rider's cases.
So, get to know it! Once you get it sorted out, you'll be able to set your bike to run well no matter where you're riding (dunes on the coast or 8000' of mountains @ 80º), and that ability will give you a MUCH more enjoyable ride!
Cheers!!