Of course, we would be reaching with the asymmetric to achieve that performance, or maybe even better. With the #1 genoa we'd need about 5 knots true to sail at 5-6 knots. With the standard 110 we'd need about 7 knots true, to sail 5 knots on a reach. A performance monohull can match us in light air, and might be faster in VMG to windward in light air, although we do point as well or better than most cruising monos and tack through 90 degrees.
It's all about apparent wind, anyway. She gets up and goes when apparent goes above 10. In 10-15 apparent wind we sail 8-11 knots. This is our wake at 14 knots boat speed in flat water, about 20 knots apparent wind with full main and 110 genoa. (Note the rail shows we're only heeling about 5 degrees relative to horizon. The windward ama is out of the water and the leeward ama's wake is to the left in this picture, making a peaked wave where it comes together with the wake from the center hull.) Conditions like this wreck 5-knot "planning speeds"