mike_orhizol's Identifications

Incredibly numerous on weathering granitic slopes; seems smaller (most plants no more than 1 cm tall) than D. bicolor and all (or nearly all) plants yellow flowered, but that seems to be the closest match in the region. Could size be drastically affected by soil quality and exposure? Seems reasonable. Still, other populations of D. bicolor have both yellow and purple flowers, hence the name. What species is this?