Hair actually retain scents better than bare skin. Your wardrobe consists of quite a few "sillage monsters" and unless you're doing half-sprays, I don't know why they shouldn't project. I'm guessing it's the old "olfactory fatigue" going on here, you smell the same thing long enough, you'll stop noticing it. Happens to me all the time - even with Opium ph.
I find the upper chest/base of neck best, it's not the side of your neck close to your nose so the habituation would take longer. It's also underneath the clothes so your body heat warms it up. 2-3, 4 if you have to, but don't over do it just because you loose sense after a while.