I can usually get by with a 39/26. Many of the mountain roads out here are long but not particularly steep. A typical 4000' climb will be mostly a 5-6% grade. When you do encounter a 10+% grade it is usually short and you can just stand up and pray you make it before you expire. Having more gears is always nice even if you don't need them but I just use what is on the bikes I buy. I never need a 53/11 but that just seems to be what is easily available. If I was building a bike from scratch I'd probably go with a 50/36 front and an 11/23 rear or 11/25 on days when I knew there was trouble ahead.