Is it just me or does test (or whatever the compound) settle in the vial if it sits for a while? I try to keep my pins to minimum (once a week would be ideal but I know some oils have to be more frequent) but it seems like the last few pins from a vial, the compound seems much more potent than the beginning of a vial. Should I be giving them a little shake before pinning? Maybe it's all in my head.