[ecomodded]

I think the real benefit in the Caps in this situation is that they do not store unneeded energy continually recharging a battery with excess power that you will never use.
Where as in the Capacitors you store only the energy you need at any giving moment and not energy for storage. Its the fast recharge of the small storage that gives the gains, the alternator is not On as often is my deduction and I think its promise.