I don't do bongs these days - but there was a time when I was around alot of Aussie's - and did alot of bongs with them - lots of raw throats from heavy coughing - as I remember -One of the last times I smoked flower instead of hash like 2 years ago I was smoking super silver haze in the bathroom out of a bong and I went into a coughing fit where I like spun in a circle and blacked out for a split second. You cant get higher with buds just makes you cough and a lot of combustible material in the lungs. Plant matter.
looks like an issue with oxygen deprivation too - since the 'erb burns the oxygen before you inhale the hit - that makes you dizzy - and I've seen many people do a 'whitey' and faint/pass-out - after a good solid bong-hit - the wear and tear on the respiratory system must be waaaay up there - hitting on a bong day in and day out -