Since my grille on the left side got taken out for me by a piece of truck tire tread :-( I got a chance to look at the replacement and was a little amazed that r.robertson claims no holes in his....???
Do you guys on the island have a special cool weather version or did r.robertson just not look quite good enough ???
Anyways...Not quite sure I completely agree with the physics you mention. I think since you are restricting air flow you will not get the same amount of air through your new grills....the air will simply go the easy way out and go around the restriction...and your car. The water hose example doesn't quite fit because the water has no other easier route to choose from...ergo higher muzzle velocity. Does the somewhat increased velocity of the air mean it's cooler....again not 100% sure on that, since what you are essentially doing is compressing the air...and that creates heat. Now expanding compressed air is cool...we all know that.
Will your grills make a difference in the environment of the engine bay... I doubt it ....but seeing how hot it is anyways I would probably not restrict the airflow anymore.
As far as the looks go....not bad but then again I like the black as a contrast on my Blaze....