In the back of my mind, I read that tempranillo tastes best when fermented no longer than 7 days on the skins, so I am testing that option out now. Climbing the risk curve, I am electing to let the natural yeast do the fermenting. So far so good, the must was pressed after 7 days, and the ferment continues unabated, with s.g. down to 1.020 today. I can taste the tannins through the sugars that are still there, and it smells like blueberries and plums now. I will give it another week, and report back...