Tire height question

[BSouders]

Why do some people run tall slicks with a deep gear ratio??  Why not run shorter slicks with something more like a 3.91 gear ratio?  What is the comparison?  are 3.91's and 28 inch tall tires about the same as 4.10's with 29's?  30" tires with 4.56??  Do you have to run a taller tire to get the real wide slicks?  Just thinking about this today and wondering why why why. 

Brian

[Mopower71]

The taller the tire, the more contact patch there is

[Mopower71]

It's not all about how wide the tire is.