My wife and I ride a tandem recreationally, and we have the same problem. Climbng is slow and tedious most of the time. Here in the Ozarks, we do a lot of climbing too. This is due partly because of the difference in height, she's barely 5-0 ( I kid her about being 4-11 7/8") and I'm 6-1. There is a considerable difference in how we deliver power to the pedals. When riding with a group, we just let them go on ahead. When it comes to downhill or level areas, they have to eat our dust!