Posted for "Chuck Jensen" <cjensen@dts9000.com>:

 It strikes me as the radio calls may be inversely proportional to the
 volume of traffic at the airport.  Counter intuitive, but consider that
 at an airport that's pretty busy, the adherence to pattern flying is a
 bit better. One, perhaps two calls establishes where you're at and who
 you're behind.  At the busy airport, everyone has their head on a swivel
 and more radios calls are not needed or appreciated.
 
 Sometimes the most dangerous airport is the low volume airport where
 pilots don't pay much attention because 'nobody is around' anyhow and
 more of the flying seems to be non-standard.  In that instance, calls
 for downwind, base and final won't add to the radio congestion (there
 isn't much to begin with) and it'll alert the dude that hopped in his
 go-fast (or go-slow as the case may be) without a preflight and hops
 right out onto the runway.  If he's listening, multi-calls are more
 likely to catch his attention.
 
 Just a different way to look at it.
 
 Chuck