Re: Thinning Silicone - Acetone?
You can absolutely thin silicone with mineral spirits or toluene and it does not effect the strength/durability of the silicone afterward. I have not heard of acetone as a silicone thinner and thus would avoid it. Either way, thinning silicone will not exactly save time since you need to wait several days after you apply the silicone for the spirits or toluene to completely off-gas before it's safe to work with again. Un-thinned silicone is usually fully-cured in 24-36 hours.
I have thinned silicone with mineral spirits to more easily coat terra-cotta pots to make them more moisture retentive but the pots had a chemical smell for several days after the silicone itself had cured.