I would say it does. If we have an irreversible process then the system is going to dissipate some of its energy as heat to the surroundings. These two things go hand in hand. Since connecting a charged capacitor to an uncharged capacitor is clearly an irreversible process we can know with certainty that the system will dissipate some of its energy.
Yeah, well, everything ends up as heat, so that's a boring trivial statement - especially since it doesn't indicate where the heat appears. In this ideal case, with only lossless components, what is the route by which it ends up as heat and where is the heat finally found? To concentrate the mind and without loss of generality, assume the components are in a vacuum.
The useful interesting correct answer for the ideal case (i.e. this classic conundrum) has been pointed to The Electrician, as I previously indicated.
What is interesting for one person may be different from what is interesting to another.
I find it interesting that
we don't need to know1 where the energy goes or how it gets there. Without knowing, we can still be certain from analysis that if an irreversible process is allowed to reach a settled, final state then some useful energy has been lost from the system, and what is more we can calculate how much energy that is.
It is supremely interesting that thermodynamics can tell us this, without us needing to know how or where that energy disappeared.
The calculations at the top of the thread do not need to be performed. The result is guaranteed without having to go through that algebra. It is fascinating to me from a physical sciences perspective that the web is full similar derivations, yet rarely is it pointed out that it is unnecessary to go through the rigmarole.
1 Obviously as system designers and engineers we sometimes do need to know, to allow for the effect this may have on the working of our system.