Key points are not available for this paper at this time.
Good tracking requires that the quintessence energy fraction slowly increase while the roll -dlnV/ slowly decreases, but is not yet truly slow-rolling. The supernova bound on the present quintessence equation of state requires either (1) a cosmological constant or other fine-tuned ``crawling quintessence'' or (2) ``roll-over quintessence'' that tracked until recently, but now became slow rolling, because of a sharp increase in potential curvature. Thus, fine-tuning is required by constant equation of state and inverse power potentials, but can be avoided by the supergravity and Skordis-Albrecht potentials and other good trackers, provided quintessence energy domination and slow roll both began only recently. This makes the time in which we live special in two respects.
S. A. Bludman (Tue,) studied this question.