Biodynamics is a strange one, I don't know whether there is anything in it, my mind tells me that it is probably a load of rubbish, but what I do know is that to farm biodynamically you have to look after your soil and your vines very very carefully and can take nothing for granted - and that being the case it is likely that an acre of biodynamic vines will have been more carefully looked after than an acre of vines that have not - whatever anyone may say.
From a soil science point of view, the roots of plants are suceptible to all sorts of chemicals and their ability to take on minerals can be hugely affected by the soil composition particularly if there are lots of chemicals in there, and fungicides such as copper based ones (allowed even in organic viticulture) really destroy the soil micro flora growing there all which contribute to less effective and less healthy roots (and therefore vines) and less healthy soil.
As an example if you were to take the 100 most prevalent microbes found in soil - copper sulphate would kill the fungal microbes (along with the algae which have symbiotic relationships with the fungi) Those algae provide nitrogen in a format that the vines can use and so on - essentially just as maintaining a healthy set of microbes in your stomach is important (so those lovely people at Yakult keep telling us) if you want healthy plants then you need healthy soil and microbes are important in that.
Anyway enough science - back to the wine! This is Millton Vineyards Viognier and it is lovely - some really nice fresh apricot and honeysuckle aromas, some really pure fruit great mouthfeel with terrific intensity and a good finish.