On Fri, 27 Jan 2012 09:56:12 -0800, DerbyDad03 wrote:
We
grabbed another dead man stick and still got quite a bang out the cap
since it didn't completely discharge before blowing up the other dead
man stick.

Effect of dielectric absorption, possibly? You short it briefly, it
discharges, but then a small portion of the original charge level appears
to come back moments later...

(http://en.wikipedia.org/wiki/Dielectric_absorption)

cheers

Jules