Ladies and Gents,
Let's face it, it doesn't take two people to land an aeroplane of any sort. There are countless thousands of aircraft with only one seat ffs. One lands it and the other , if on a multi crew aeroplane , does all the ancilliary stuff. Airline crews fairly regularly practice, in a simulator, flying an approach and landing with the other crew member 'incapacitated', well we do anyway.
The practice pays off, around five years ago I was on a SYD-NRT sector in a B767, and the Captain was incapacitated with the symptoms of kidney stones. Medical advice was sought and he was directed to 'have nothing further to do with the operation of the aircraft'. I, being the F/O, now had the chance to log some command time.
Well I took over anyhow and completed the flight to NRT in weather conditions which were right on ILS chart minima, at night in rain with a S/O who had never been to NRT. He was less than helpful because of his inexperience.
It all worked just fine, the approach and landing was completed, the aeroplane was parked and shut down, the ailing Captain was seen to by medical staff and off to the Truck the rest of us went.
The reason modern airliners have two sets of controls and require two pilots to operate them is not because they are almost impossibly difficult to operate but for the very reason that this thread exists, in case of pilot incapacitation and nothing else. If one pilot can't function fully then the other one takes over all the duties, for which they should be trained and more than capable.
Of course things would get a little more interesting if you also had a technical problem to deal with but that falls into the realm of 'multiple failures' which is generally not considered or trained for but sometimes does happen.
Regards,
BH.