Yes...We average around 100 miles a week. Some touring, road biking, mountain biking, single track and down hill. Not always the fastest on the down hill but she's doing it.
Some days she pushes me to pick up the pace.
On our last ride we were about 40 miles in to it when a group of about 10 guys past us. We got into the draft and she was able to hold a 24 mph pace for 6 miles.
She said with a smile on her face that was a little scary and fun.