"Horrible idea". Interesting how all of the fastest lnf powered cars are running our horrible design.
I understand the concern about fuel puddling, but it is simply not a factor. If we were using the 5th injector to fuel the engine at idle, then it would be a poor design. Fortunately, that is not what we are doing. At full boost, air is rushing through the throttle body at over 100 miles per hour. Take a blow gun spraying compressed air and release a drop of water into the stream. See if it puddles on the floor.
Fwiw, we tested both designs extensively. We don't just theorize about what works better.