Some actual research is starting to come out about flushing. The more recent study i saw done by industry researchers showed zero difference in cannabinoids, terpene content or dry weight yield in flushed vs not flushed. The non flushed even scored slightly higher in a blind testing panel, but it doesnt say whether it was smoked in a pipe or a joint, and again i suspect it was a pipe but havent been able to comfirm it. The flushed pot did show lower levels of chlorophyll, and that was about the only difference noted.
This was an interesting video. Im still extremely hesitent to try not flushing again as a strictly joint smoker that is enraged when my joint burns out. But i might experiment again someday on a smaller scale.