That's a good way of training yourself, I weened myself off the left-pinky control key by doing the same thing. I now press it with my left thumb - which is easy on my new Kinesis keyboard. Moving your hands off home row to hit arrow keys also slows you down. It adds about 500ms latency to your workflow every time you do it.
I actually trained myself to use the arrow keys because of my RSI. Moving my hands away from the home row slowed my typing down a touch and alleviates some of the constant pressure on the fingertips.
But now that my RSI is manageable as well (two words: wrist breaks) perhaps I should try going back to hjkl.