Fix is right some slippage would be possible but only be at low speed, once underway it is being force fed by the prop and forward motion of the boat. Look at all the dual tube ones that hundreds of guys have been running for years with not complaint, the only reason to position the pickup one side or the other is to take advantage of the flow off the blade tips for maximum cooling effect. I have wondered just how much difference that makes once you are at higher speeds! Think for a moment how is it possible for any thing behind the prop to cause anything more than drag at speed, nothing can flow backwards against the water flow standard physics of hydrodynamics!
No matter what your beliefs are "GOD BLESS AMERICA"
Fully retired marine tech near 60 years in the biz.