Pumpkin,
My Fuji has a double (36/46) up front and a 12-25 10spd on the back. At times, I'm also wishing I had a granny on it! Did a nice 36 mile ride yesterday with rolling hills, some pretty steep and long, and though my knees are good, my thighs were getting fatigued. I find I sometimes have to stop for a few minutes and rest my legs, then I'm good to go - almost like they got their second wind, and I just run up the hill no problems. I guess that ultimately, it will make me a better/stronger climber - in groups rides, I pass a lot of people only because my bike can only go so slow because it doesn't have a granny; if I pedaled any slower, I'd literally fall over