I agree about getting people to read and reread! I had.... oh, let me see. My mother and my sister (both doctors), my father (an author), my girlfriend, and my academic mentor read it over multiple times. I can't even tell you how many times I rewrote and revised. I basically LIVED my personal statement for about 2 weeks... I would be tinkering with it multiple times a day, sending it to various people, compiling their comments, getting further opinions, etc. It was truly a group process (I mean, it was very definitely MINE, but every phrase had been thought about by other people to make sure I was saying what I wanted to say, in as simple, elegant, and clarifying a style as possible).
I definitely spent a lot of that "revising" time strategizing- what about my application did I want to emphasize, what less so? what was most effective to talk about? I had so much more to say than I could fit... it really becomes an exercise in precision and clarity.