From my experience, it also depends on the phero-blend that I'm using. I never experienced any ghosting with A-nol heavy blends. But it happened several times with B-nol heavy blends or when I used lots of cops.Some of my phero sprays are very concentrated (x3) because at the beginning I thought 'more is better'. But over the time I learned that sometimes 'less is better'. Now I prefer phero sprays in alcohol x2 or x1 concentration. I found it's more effective when I use about 3 sprays of x1 concentration rather than 1 spray of x3. This makes it much easier to find out the right amount.
Drinking lots of water which might help flushing out the excess amount that the body might have absorbed, that's also an interesting point, Beccah. I never thought about this before, but it makes sense.