--You should prepare identically no matter which one you believe more.--
Nonsense. If I evacuated every time I was in the cone of a projected hurricane, I would have to spend half the year in Michigan every year. If you live in Florida, you have come to accept hurricanes as part of the bargain. Live here long enough and you will sustain hurricane damage. That is a fact of life. Evacuating when the eye of a major hurricane is landing within 30 miles of you is far, far different than running whenever you are in the cone of probabilities.
While I understand the unpredictablility of storms, it is the forecasted line that I do focus on. The closer that line is to me, the more nervous I get, and preparations will vary depending upon the updates.
If you live in, say, Cape Coral, and it matters to you that a 4-5 day forecast track has a storm going over Cape Coral, or going over Marco Island, you really don't understand hurricanes or hurricane forecasting.
This is the cause of people being surprised by storms when they had no reason to be, and then taking out their frustration on the forecasters.