Do I NEED a Yeast Nutrient ?

As I mentioned in another thread, I washed my last batch of yeast (Cry Havoc), but wound up with a very thin layer of yeast at the bottom of my jars. I'm planning on using this yeast in a Pale Ale very soon, but I'm concerned about the amount of yeast.
A friend of mine, who owns a mom-and-pop Italian specialty store, gave me a small jar of Carlson yeast nutrient (Urea and ammonium phosphate) that he uses when he makes wine, and suggested that I might want to try using it. Considering that he makes wine, and not beer, and he rarely even drinks beer, his advice is a little...suspect ?

SHOULD I use the nutrient in my starter, or if I start the starter off small, and step it up over a day, will that give me enough viable cells ?

Wine makers are going to be biased towards adding nutrient, since must is generally nutrient poor.

All malt wort is not, oxygen is more important than exogenous nutrition in the case of underpitching all malt wort.