I think a person's gameplan and decision making process changes quite markedly depending on where they rank. My guess, and it is only a guess, is that you went into 'protect my rank' mode at 6k and avoided the riskier purchases that others took. I was still trying to gain, so I had less pressure on me. And at the other end you have people trying to break into top million who are going off the reservation with their purchases. Obviously it could also all entirely be luck but I don't believe so. I think we do put the blinkers on relative to rank.
EDIT : Actually, from looking at yours closer, I think it boils down to choosing to use the FH in 29. Had you used it this week instead, let's assume you'd have broken the ton. We'll give you a hypothetical 110. That puts you pretty much bang on with me around the 30k. So don't be too hard on yourself. That one decision properly **** you over.
Just look at the weekly overall rank of the person currently sitting 5th in the game. Imagine the pressure they've felt every week. Not sure that would be good for my health