One point cannot be made often enough -- when you retire, are you going to be withdrawing a fixed inflation adjusted amount on a regular basis, or are you going to be withdrawing a fixed percentage of your portfolio? This is not a semantic fine point. If you need a fixed amount, plan on withdrawing no more than about 4% of your starting amount in inflation adjusted terms. A fair dollop of bonds won't hurt in this situation.
If you can be more flexible and spend a fixed percentage of your nest egg each year, then you can indeed keep you entire retirement stash in stocks and spend 5% annually. Just remember that your stipend will likely fluctuate wildly over the decades of your retirement. Keep a few cans of Alpo in the cupboard if you decide to go this route.