"Are there cannabinoids that are not able to be reached through vaping or are they just leftovers of the ones being vaped? (I vape at the 11 o'clock position and finish the bowl with a draw at 12 o'clock.) Thanks!!"
The general consensus is that AVB still contains anywhere from 10-30% of the cannabinoids. I personally like to vape until the flavor is gone and then save the rest for making butter. That way I get to enjoy my flowers and then take the left overs and make some awesome butter. You could always turn up the temp to get more of the cannabinoids but since vaping is already far more efficient than smoking, I'm not mad that there is still a little left over on the AVB.
Pretty thorough, but simple instructions to make cannabutter.