I actually think the oils that work are ones that evaporate and are related to the kinds of oils that are more flammable.
If you took water, a sponge, whether a dish sponge or a TT sponge will absorb the water and that would cause the sponge to expand.
But that would not give you a boost effect. This is why some oils make the rubber feel mushy. This is also why you don't want to use too much mineral oil (baby oil). Why it can make the sponge feel mushy.
The oils that give the best boost effect evaporate fairly quickly like Paraffin or even more toxic oils.
That they evaporate quickly makes it so the pores in the sponge have more gas in them so the sponge is more springy. But this is also why the boost effect does not last that long. The oil evaporates.
Oils that don't evaporate will saturate the sponge pores. This gives an odd effect that isn't quite ideal for boosting.
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