Yes and no. The strategy is strong. The rush I've seen most myself is the one coined by krath, a Sova and a Marza. Similiar situation.
I say yes it's hard to counter because of the bonuses the carrier caps get to their strikecraft.
I say no because carrier caps are like any other caps. They make lovely gigantic targets. Espcially early on. I personally am playing a lot of TEC lately, and love using the Akkan. Get a decent contingent of flak out for the fighters, get the lrms out quick, and get the Akkan to hit the caps with ion bolt (if you can time it better to counter abilities all the better).
Boom. Dead Caps. It's a new strategy which I think is flustering people. The first time it happens, the odds are you were an easy unprepared target.
Personally, now I've had to readjust my starting rush strategies. Poeple hit harder and hit faster early now. If you're not building ships early on you had better be waiting for your research so you can build more.
Look at the stats of one sova compared to 6 assailants and 4 flak. Those six assailants do 98 dps out the gate, or 73.5 dps against caps. A level one sova does 33 dps and then the three squadrons do a bit over 30 dps, 60 dps if against light armored targets.
Hmm....That's 73.5 vs. 93. I think I just disproved my point. Yes I know I left flak out of that arguement, but they'd be going after the fighters. Oooookay, let's go with light frigs.
5 Gardas and 6 cobalts vs 1 sova
6*9.5=57 dps out the gate.
The sova does 33. The 3 squads of fighters do 30 dps, but that's reduced to 15 (50% against light frigs), so that means
57 dps vs. 48 dps.
Of course I'm leaving out abilities here. The allure of carrier caps is quite strong, but really, I have a hard time arguing against having more than 2 caps witihin the first thirty minutes. You're eco suffers because of how much you pay to not only get the capital ship slots, but to get the actual ships too.