With all due respect to you, what's the point? You will have invested quite a bit of money in parts to obtain a very minimal change in gearing. I doubt you'll even be able to feel the difference.

If it was my bike, I'd slap on a 50/34 or 50/36 compact crankset. If you think that you use your 53/12 a lot now, get a new cassette that has an 11 tooth small cog and it will give you about the same high gear ratio. Otherwise just stick with what you have until you can see how the easier hill climb gear feels.

The drawback to compact doubles is that they frequently make it necessary to shift a couple of rear cogs when you change front chainrings. If you can figure out a chainring/cassette combination that lets you do most of your flatland riding in the middle of the cassette, you can minimize that issue.

The good thing about compact doubles is that it's a fairly economical way to regear your bike. It doesn't make sense for a guy like me to have essentially the same gears as Lance anymore than it would be to put a Ferrari transmission in a Volkswagen. When I changed to a compact double I got rid of the highest gears that I never used, added some easier hill climb gears that I needed and the only thing that I had to buy was the crankset. I love it.