we mixed bud (like .6) with shisha in a hookah. shit was ill. you could taste the bud but also you had the thick smoke of the shisha. got 4 of us toasted for a good 2 hrs....but then of coarse we all smoked an L that night so it was all good.
I've done it a couple times, in all honesty I would much rather keep the two seperate (shisha and herb). The only way I would voluntarily do it would be if i had a bunch of mids but your not gonna see me mixing dank herb into a hookah.