Interesting. That's basically how I do it. I think it's because I have ridden single speed bikes for a long time, so when I move to my geared bike, I don't like to occupy my ride with constant gear changes. Usually, I keep the chain on the middle cog of a 9-speed cassette, and do most of my shifting up front on a double chainring: Small chainring for lower speeds and upward inclines, big chainring for faster speeds and downward inclines. So, on relatively flat terrain, I basically treat my bike as a two speed. Only when I hit steeper hills do I begin to shift up and down the rear cassette. This is not the most efficient use of the gearing, so I would not claim it is the "proper" way to shift, nor would I necessarily advise others to use this method. I just know it's how I like to ride.