I started a thread last summer that started a huge debate on this very issue and kind of hinted at Erik's opinion on this AND really changed my game and opinion on this issue a lot (13 to a 9 handicap in less than 1.5 months).
I'm doing it the same way this summer and plan to get even lower. I'd put money on it that I have an even par round of golf by the end of the summer.
By the end of last summer, when I had to stop playing and go back to college, I had started hitting 10-13 GIR during my average round simply because I put so much work into my PW-4I. I very near immediately saw a drop in 3-5 strokes when I started practicing on those iron shots for the majority of my practice time as opposed to short game (like I had always done in the past due to being told old and incorrect ideas). Granted I was on the range 3-4 days a week, I still feel as though I made vast improvements. The other thing was, the short game stayed just as good as ever, as did my putting (in fact I really didn't practice putting at all, and still putted well). The one thing that kept me from going even lower was my terrible driver, and I started hitting 3W off the tee instead of driver which I expect to change by the end of this summer.
And on top of that I can't tell you how much fun it was having rounds where I was hitting that many GIR. Based on my experience last summer, i'm convinced that this is THE best way to allocate your practice time.