Vevak,
1) On what do you base that claim on? My research of the Caspian Flotilla in the modern era makes it pretty clear the vessels are NOT meant to serve as a reserve for any other fleet. While they CAN move via the river networks to the Black & Baltic Sea fleets, it's not a simple task and would leave them very exposed in a real time of war scenario. The Caspian Flotilla's primary duty is to defend Russian interests in the Caspian Sea region and to some degree, project power into the ME (via Kalibr LACMs). So you claim has no basis and as such, is pure rubbish.
2) Why do you keep talking about Iranian designed Gatling gun systems? I'm talking about Iran reverse-engineering the AK-630. There is no need to reinvent the wheel of making a Gatling gun system function accurately on a moving naval vessels, since the Soviet engineers did that decades ago! If anything, by reverse-engineering te AK-630, Iran could perfect their own domestic designs. Also, just as a FYI, the kind of stabilization needed for a CIWS is virtually identical to the kind needed in a medium caliber naval cannon...such as Iran's Fajr-27. So once again, this "point" about Iran not being able to manufacture a stabilized Gatling gun based CIWS is completely without basis in reality.
3) Here's what's wrong with your cost theory with "smart rounds": You're trying to have your cake and eat it too. Which I brought up how expensive such rounds are, you claimed that Iran could surely manufacture them much cheaper than existing designs. Guess what? That same logic also applies to the more traditional "dumb rounds" too! So if such a smart round costs the US 10 times what a dumb round would cost and Iran can make the smart round for half the price, odds are they can make the dumb round just as cheaply, maybe even more so! So once again, your point here is also without basis.
Not saying Iran shouldn't pursue such technology, just that keeping the clearly inferior Fath-40 and not investing in a more capable Gatling gun based system which Iran ALREADY HAS ACCESS TO AND HAS FOR 25 YEARS is not a logical argument.