increases pilot workload and therefore reduces spare mental capacity and situational awareness.
Oh come on now! Don't airline pilots have to undergo all sorts of aptitude tests to prove they are the Right Stuff before being offered a job as a pilot in an airline? What's all this "spare mental capacity" rubbish? They are given hours of training in simulators and that cover all sorts of emergencies on almost every simulator trip. Doesn't that training give them an abundance of "spare mental capacity" to do a straight forward visual approach and landing?