Darcy Piceu crushed the women's R2R2R record on April 23, 2011, 8h25m26s. The record had been lowered to 9h12m just 4 days before by Devon Crosby-Helms and Krissy Moehl. Darcy ran with Dan Brillon until the bottom of the South Kaibab trail on the return, where Dan had some knee problems and let her go. Sue Johnston, who was also running the R2R2R at the time, reports that she and Chris Scott observed Darcy & Dan on the descent of South Kaibab. After reaching the river, Chris returned to the South Rim via the Bright Angel Trail, then took the shuttle bus to the South Kaibab trailhead, arriving about 10 minutes after Darcy finished. Dan and Darcy's husband Bob Africa arrived about 15 minutes later. Dan reports the following splits from the run:
Caretaker's House 2h37m
North Rim 4h06m
Caretaker's House 5h00m
South Rim 8h25m26s
Here's a link to Dan's public Facebook page on the run.