I've done the same calculations re airspeed difference between the wings and concluded that flies, dirt, rivets, etc. would mean more than that.
The books normally state angle of attack is diffeent, but don't explain !
Angle of Attack varies as a vector with speed, and also with the upwash induced by the wing. Upwash is in turn variable with the wing configuration, airflow velocity over the wing, and angle of attack. Increase angle of attack, increase downwash behind the wing and upwash ahead of the wing, and angle of attack increases beyond the simple angle made by the free airstream and the wing chord line...local angle of attack is greater because of upwash.
Increase the airspeed over a wing or section of wing, increase lift, increase drag, and you also experience a change in AoA. Change the configuration of the wing, such as lowering an aileron, and with the mean aerodynamic chord change and effective camber change, you've got a change in upwash and downwash, as well as AoA.
Additionally, as the aircraft is rolled into our out of a turn, changes in local AoA vary with the rising or descending wing, and in a turn when some degree of spanwise flow occurs, changes in AoA follow, along with changes in the lift component of any given wing cross section at any given time.
A simple example of a change in AoA, and lift and drag can be seen by lowering an aileron. As the aileron lowers to raise the wing, effective camber is increased, drag increases and rudder may be required against the drag created by the aileron. This drag, adverse yaw, is part of the reason that rudder into the turn may be required when rolling into the turn. As lift is increased on the wing, drag is increased, and the wing is experiencing an increased AoA. This is one example of one reason AoA may be locally increased during a turn, or turn entry, or sustained in a turn...depending on the design and requirements of the specific airplane or wing in question.
Remember that the increase or decrease in lift and drag isn't linear, and varies with the wing planform...what one airplane sees as a big change under a given set of conditions (airspeed and bank) another airplane will see as a little change. Add numerous other variables ranging from airfoil to control positioning to dihedral to sweep, wing planform, and even center of gravity, etc...numerous factors come into play which affect the stability and habits of the airframe.
The following article contains a couple of tables and graphs using several different wing planforms which might give a little insight. You can see that the drag coefficients go both up and down, depending on what type of wing is in use, of several demonstrated in the computer modeling.
Drag in Circling Flight
In a climbing or descending turn, the differences in AoA and the lift produced are a little more pronounced, and may be a little more noticable. One may not notice it in level flight, or the specific airplane may not require aileron into or against the bank...or it may only be noticable at certain degrees of bank, and not others. During a climbing turn, the outer wing tends to have a higher AoA, and during a descending turn it's the opposite.
-- with all else equal, descending turns are more stable than climbing turns.
They're not, though it may feel that way.