I assume control loads would be a bit lighter...The chart for the unboosted vs boosted ailerons is somewhat deceptive (unintentionally). To compare the unboosted vs the boosted roll rates you have to take the unboosted curve (upper) and overlay it on the boosted curve (lower). If you do this you will see that at low speed the chart curves are basically the same from ~125 mph to ~250 mph. Ignore the time to bank to 90° numbers to the left of the unboosted curve (upper) as they do not apply in this case.
This is the only video of the aileron movement I have seen off-hand:
The hinge type was of the piano variety, where (if I understand it correctly) the entire surface moves around a simple arc centered on the forward hinge pivot. +25°/-20° total movement up/down for the P-38. From the drawings I have seen the leading edge of the aileron is not shaped like an airfoil, rather more of a concave shape. No forward movement or lift/lower of the leading edge is present (that I can see), other than the slight protrusion of the upper/lower leading edges of the aileron when moved up/down through the simple arc.
Also, I could be wrong.
In the book Jungle Ace it is described how some P-38 pilots in the PI went to pick up some new P-38L's. Once in flight they found them so sensitive as to be almost unflyable. They had real concerns about being able to even land and one pilot said he was going to point it over a big lake near the base and then bail out. But one said he had found an "Aileron Boost" control and when he switched it off, things went back to normal. No one had told them of the boost feature and it apparently had been turned on during ground testing and then not turned off.