Well, it was just summarily dislodged from my not very scientific brain for good.
I disagree that pressure/wind relationship is a myth. Rapidly circulating winds reduce the pressure inside - the faster the winds, the more the reduction... but... and this is important to note: the spread of the eye can also affect the other two readings. The tighter the eye, the closer the relationship agreement between pressure and wind speed (approximates a tornado). Katrina and Rita both have large eyes and the relationship evidently begins to break down. As the eye tightens though (which is indicated by the latest Vortex message, I expect pressure to drop more and wind speed to be found increasing. Not sure if it will regain Cat 5 status, but it stayed a Cat 5 long enough to build up a substantial water dome, and the pressure hasn't risen all that much, and seems to be on its way back down. Still about 36 hours out though so anything is possible.