Really? I don't know about the "silicone or not to silicone" thing, but as far as the tolerance bit: I did some looking up and this is what I found about the subject....note(these are statments from people other than myself)
"Pheromones are natural products of the human body. You already sense them daily on your own body and those around you. They're basically messenagers of social and sexual signals and can invoke a biological response, an urge if you will. Unlike insects and lower mammals we can and usually do choose to ignore these urges. It also depends on the person,some people are more sensitive to phero's effects than others--it can seem to work like magic at times, and with other people it may have a more muted effect, perhaps if the person is more the strong willed type.
The initial exposure to a strong pheromone is often surprising and may catch you off guard. Once used to it, it comes routine and can be easily ignored if you choose to.
Artificial pheromones are no different in this respect. They amp things up but the laws of the universe are still intact. However, you can rotate mixes to maintain some sense of surprise. I use 4 or 5 different mixes in rotation across a couple weeks.