Frost came into the second round with a one-shot lead and stayed hot thanks to seven birdies during his bogey-free round, ending the day at 14-under 130 through 36 holes.
That was two better than 2011 champion John Cook, who eagled the par-four 18th to secure sole possession of second place at 12-under with his second straight round of 6-under 66.
Third place at minus-10 was claimed by Kirk Triplett following a round of 4-under 68.
Bernhard Langer (68) held fifth one shot further back.
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