A quote from Captain William Wainright, Chief Pilot Airbus Industry
USE OF RUDDER We also spent a lot of time dis-cussing the use of rudder. The exist-ing training courses all emphasised using rudder for roll control at low speeds. It is true that the rudder re-mains effective down to very low speeds, and fighter pilots are accustomed to using it for “scissor” e v asive ma-noeuvres when flying not far from the stall. But large airlin-ers, with all the inertias that they pos-sess, are not like fighter aircraft. Based on our experience as test pilots we are very wary of using rudder close to the stall. It is the best way to provoke a loss of control if not used very carefully, particularly with flaps out. We finally got the training managers to agree to play down the use of rudder in their existing courses. But we do not say never use the rudder at low speed. We say that, if necessary, the aileron inputs can be assisted by coordinated rudder in the direction of the desired roll. However, we also caution that “ex-cessive rudder can cause excessive sideslip, which could lead to departure from controlled flight”.
End quote.
That can be found in FAST #24, a discussion of aircraft upset.
If rudder is the best way to " provoke a loss of control" in an upset, how could it be beneficial in the stall? I do agree with you were we discussing straight wing low speed trainers, but not large swept wing turbojets.