Thats just rubbish. For a start, Wayne is in much better health than either of those two at the same age. Not even comparable really. You are just picking out a couple of blokes who coached for a long time. Every individual is different. Some people have had enough at certain stages, others haven't. Wayne's clearly still a quality coach and feels he has more to give. How long that lasts we will see.
To say its a disaster of a decision is laughable. You couldn't get much better unless you are getting Bellamy or Robinson as your inaugural coach. They wont scrape together a squad either. They will recruit pretty well but lets face it, Wayne is there basically to help lay the foundations. It would be stupid to think they are going to be premiership challengers in their first 4 or 5 years. Its a totally different job than when he took over the Broncos.
I'd still like to know what makes you think he is kidding himself that he will last 3 years? He is physically fit, he's mentally sharp and is still passionate about the game. I honestly cant see at this moment in time how you are coming to that conclusion.