I mentioned this in the liger thread but I think that most of the mmj waste happens with the way that most people dab.
Most people tend to cap while they inhale and when they run out of breath and do a first exhale, take the cap off. Some even take the cap off during the inhale (this is extremely inefficient in low-temp dabbing, as your vapor wants to take the path of least resistance which is rising above the nail)!
This means that all of the oil that hasn't yet boiled into vapor gets wasted in the form of vapor pouring into the air above the nail. I believe this may be a hangover from the quartz dabbing era, where the end of the dab generally tasted like shit and so most people accepted wasting it to taste it. I disagree with this approach, IMO one should take smaller dabs if their nail isn't capable of making the end of a larger dab taste proper. No need for waste, just take another smaller dab and enjoy taste without the waste!
For SiC, this isn't so relevant since SiC vaporizes oil the quickest of any surface and the taste is more consistent throughout the hit than quartz. You don't need to take much more than 1 long rip to finish a given dab on SiC at a tasty temp. If you do need an extra half rip to finish the hit after the first exhale, leaving the cap on to save your vapor in the meantime won't taste bad (there will be a slight dip in flavor)
With sapphire especially, we need to rethink how we dab to get the most efficiency and best flavor from our meds. Lower temps, longer 2-3 rip bowls leaving the carb cap on between rips until you get no more vapor are best suited to sapphire. With 5 star full melt, however, I would not inhale until there is no vapor left: instead you might stop ripping until you start to taste any non-melting residue cooking at all.
A lot of people, even with next gen e-nails might save a lot of money by changing the way they dab!