I think you might have missed a few variables before coming to your conclusion. Most cars that run a regular fan are stock, or nearly stock motors (meaning they make less power, and generate less heat). Most guys that are building performance engines look for every bit of power they can get, so going to an electric fan is natural because it free's up horse power....and higher horse power cars make more heat....just something to consider before drawing conclusions.
My car used to run hot with my stock fan, then I yanked it and put a 16 inch electric fan on with no shroud....it still ran hot. Finally, I tried a Chevy HHR fan on my radiator (fully shrouded, pulls a crap ton of air, fits a 22" radiator perfectly, I got mine for 50 bucks new through Rockauto)....it ran WAY cooler after that.
Now, after switching from pump gas to e85, i don't even use my fan very often unless I'm sitting in traffic. The cooling power of alcohol is awesome.:D