Keep in mind oxide thickness reduction will increase capacitance.
Charge say, a 16v cap from 16-20v thru a 1k-10k resistor til cap voltage equals supply voltage.
Then measure the capacitance- oxide may be closer to original thickness.
Yes, there's other factors involved here, not the least of which is the fact they're "f-yoos," but it's an attempt to go back to at least one "known". Such craps and their oxide thickness reduction will give a false-high capacitance when tested.
Which you know already...
