And I would add "test your boat", as well. I'm surprised that there are serious gear failures before they've even reached Cape Verde. And as for the guy dropping out because he finds he doesn't like single handed sailing - words fail me.
I've said before somewhere, and I'll repeat it here - if you're going to make a long ocean passage, test yourself and the boat by making one at least 10% of that length. If you're aiming to get around the world non-stop, that would be something like UK>Azores>UK, or something similar. Not unduly demanding, but it would expose the obvious weak links.