The origin of crow braking is in the world of F3B competion gliders. These evolved at a time when all moulded machines where becoming the norm, and these were the low drag airframes. Part of the task for these competions is a spot landing, timed to the second. The best way to acheive a succesful spot landing is to do a steep approach, but for this a large increase in drag is necessary. Large flaps that depress up to 90 degrees evolved, but these can cause large pitch changes, especially as the airspeed increases. The use of raised ailerons then evolved in order to reduce the pitch change, as well as add a little more drag. A secondary effect is to sometimes give the ailerons a little more bite. Whilst the rule for flaps is "as much as possible", the angle the ailerons go up needs careful fine tuning to achieve the desired results.
As has been said here the actual effects vary dramatically between airframes and in partucular with wing sections. Despite what has been said here, raising the ailerons is very effective in some aircraft at reducing tip stalling and at least one full size glider reflexs the ailerons up for evey landing specifically to reduce its rather nasty tip stalling tendency.
Pitching the ailreons up alone is not crow strictly speaking, and the angle necessary to get a useful result, may in some aircraft be so much theat it reduces aileron effectiveness.
My new Eurousport is significantly lighter than my old old Mk1 version. Nor does this one have an airbrake and it does float on.rather. I intend to experiment with crow to see if I can fix this. Clearly on thsi model equal amounts of down on the inner surface and up on the outer surface will be the starting point.