Howdy,
Sorry gentlemen, my "push vs pull" assertion is primarily in reference to our float installations where we depend on the electrics for total airflow (parade speeds yield no useful flow from forward motion). It is however, based on quite solid experience and I felt might hold pertinence to low speed cooling on the street. Our theorizing is after the fact, in our attempts to understand "what just happened". If it flies in the teeth of other's hard experience then it's conceivable we don't yet fully understand what we have.
In this sort of situation having the blades bite into clean air and pressure the radiator face is sufficiently more productive than having'em sucking at the backside in disturbed air to more than offset any surface area loss (while shrouding would surely help to some extent, that's not practical on the float). We do still have to operate one of the two animation radiator fans in pull due to space limitations, and that one clearly and consistently cools less than its pushing brother when we run each of'em alone.
We've surmised the fan body itself not only doesn't pull air through the radiator at the center in pull position but also has a small air damming effect of its own from the same motor body in that position (this should be readily overcome in street practice due to external airflow). This appears to offset to some extent the "area loss" of the pusher. Add to that the lessened "bite" and the lower efficiency of suction vs pressure and it seems to cover the performance we exhibit.
As the airflow generated by forward motion in a normal car renders the fan redundant at a given speed anyway, this gives an upper limit to the pertinence of the point. From "parade" speeds down to full stop I believe the fan body blocking significant airflow succumbs to our float experience , giving a lower limit to the point. The speed band between the two, where incoming air provides useful cooling but doesn't yet exceed the fan's output should indeed be a valid area for the point. As I haven't run an electric in pull on the street I cannot fairly compare the two in that band.
All that being said though, I've run the few electrics I've used outside of float building in push position as well, with fine results, and will be running another pusher in Cassi. This leads me to consider whether we're "Straining at Gnats" (required reading for legals as I recall, along with "Swallowing Camels"
. Sorry, couldn't resist) on this one as it applies to the street.