One important note on that though: when you change a setting on a carrot, move the plants around, transplant or even just bump up against a pot; you can create an air gap between the carrot and your planting mix. I think this is the main reason people get run-aways - the air gap makes the Blumat "think" the soil is dry when it really isn't. So if any of those things happen, I think it's a good idea to pour a little water around the carrot and pinch the potting mix against the ceramic cone.
What do you guys think of soil drenching after installing your blumats? Any thoughts?