ok... the throttle body is a strange "place." it contains, and controls vacuum. ice can and will form at temps as high as 50 degrees because of the pressure differential and the air flow across the pressure boundary, otherwise known as the throttle plate (or butterfly).
the heating provided by the coolant running through the throttle body is there, not only to prevent icing, but to provide a stable temperature range for the intake air. i seriously doubt that the efi has enough range to properly charge ice cold air with fuel. sure, that's done at startup, but it's not done by variation of injector timing and fuel pressure, which is the normal method of matching mixture to conditions. i believe there is a "choke" injector, somewhere in the manifold, that handles extra fuel required for startup and warmup?
i remember seeing this, in its crude and initial form, on my '83 ford 302. it had a thing that redirected the intake air past the exhaust manifold when it was too cold. it was mechanical and operated via a spring in the airstream. even in '83 they were seeking to limit the range of temps in the intake air...
these cars operate on the ragged edge of running too lean, as it is. if you introduce cooler air, it will require more fuel. and yes, cooler air has the capacity to produce more power as it contains more oxygen (because its more dense). however, if the greater amount of fuel is not delivered, the result is an engine that runs really hot, because its too lean.
i won't be doing this, myself. if you do, well, good luck. maybe after you grind your 24 valves or replace your motor you'll have some respect for people that really are engineers, and really do know how to design a fuel system.