Yes, smaller stabs are more lively, and at some point a lot more difficult to ride - that was not the question as such as we all know that I think.
But it seems that many riders (brands actually) got way too big stabs, as soon as riders have learned to foil quite good ?
That was my point, and would like to hear experience from others who rides (or have ridden) with different stabs (horizontal and/or yaw) on the same foil.
And for sure I can only advocate freestylers/waveriders to put a smaller stab on immediately, if they havent done this or tried it yet
At some point it will become too loose and feel "slippery" yes, also in terms of yaw, the tracking gets lost - just like having too small fins on surfboards/windsurfers
But it seems to be at an incredibly small size this happens, so there is lots of room for agility improvement on a given foil without sacrificing low end (as you would if you took a smaller more agile frontwing)
Reducing aoa (you actually mean increasing but I know what you mean Plummet) does not have the same or any effect regarding agility, but one could get an idea if the foil is more stable than needed indeed, agree.
But a long way from such a test, to a real ride with smaller stabs (both horizontal and vertical, and swept tips is the same as vertical).
For me, carving (preferably in any kind of waves) is EVERYTHING, this is why I seek the best tools for this