SoCal - the point you make is exactly right.
However, it does seem odd that Apple did not consider sun light readability. It seems to me the iPad is very much sold as a lifestyle product - the sort of thing you might sit in the garden to watch a movie or read a book and yes even on your lounger on the beach and not just in the 7.30 carriage to London Bridge attempting to impress the other passengers.
C'est la vie - it isnt sunlight readable and whether or not it might have found a niche as a pilot's companion the fact remains it would appear to be useless in the cockpit. The thread is therefore justifed as it saves people considering it as an option and being disappointed.
(Edited to add Bose has an alternative point of view, so perhaps the jury is still out - my opinion was based entirely on the rest of this thread and the video)