My experience is that ugh fields are invariably unfortunate in their effects. While it might indeed be useful to have a disgust reaction to candy or video games, the "ugh fields" seem not to be visceral disgust, but visceral, conditioned-pain-induced tendencies to cut off thought. Shadows you hide from in your own mind.

My experience is that the more ugh fields I can clear out, and the better I can get at not accumulating them, the more I can actually honestly think, can notice choices rather than just feeling stuck, and can find myself with energy to take on new projects. That is, there seems to be a general property of "having a clear mind" or "facing things" vs "hunkering down with willful tunnel vision lest I run into something painful", and allowing or clearing out an ugh field around an email or a broken conversation or whatever it is affects my overall state, not just that one area.