This practice was on archaic aircrafts like the DC3s may be some Russian aircraft like AN12(not sure). That too the concern was flap asymetry or runway on one side causing a rapid roll which may compromise aileron Control. But definitely not for stall considerstion. All today's aircraft have protections which make this concern superfluous and none of the airliner documents mention a word about it. Observing some obsolete caution because of habit is not the way to go.