I am trending to agree with the do some runs with it off and see how the boat performs. I've done a bunch of reading and seen arguments for both and against its use. It will be interesting to see how mine performs.
In thinking about it, I would tend to think the the two would fight each other. The tabs are basically lifting the stern or holding the nose down (depending on how you look at it) and the foil is trying to do the same thing but by and opposite approach to an extent? For instance if you trying to keep you bow down you would drop your tabs and or trim the motor down which with the foil would help "lift" left your out drive or back of the boat. so in that sense they're doing the same thing. But now if you want to go faster you would retract the tabs in most instances, removing the drag. But on a hydro foil you would trim up the motor which would cause you bow to come up so there is less hull in the water meaning less friction (in theory) biggest problem there if I'm running both the tabs are still there "even retracted" helping hold the stern "up" while the foil is trying in a sense trying to push it down? Which probably causing several issues ie un-needed stress, slower speeds and more fuel consumption, this is all in theory of course. But until I can get it out this week end I won't know for sure, guess I'm just wondering, is my thinking out of line on this?