It may not be the interesting issue, but i think cost IS one of the driving forces in this debate. dat19 may not be included here, but from my observations, maybe not to the same degree on ZG, but certainly on HFC in abundance, it is predominantly those with cheaper equipment that are ardently proposing DBT (despite many of them not actually employing the method themselves it must be noted), AND predominantly those with more expensive gear that are 'indifferent' to such a method. Which is why i raised the point with Lawrie. Perhaps i am mistaken, but that's definitely the impression i get.