From: San Diego
Hi. I'm "one of those people."
I'm a bit aggressive as the Allies in the early months. And yes I've lost CVs, but no I haven't quit in my allied games. I've actually had a bit of success with raiding the KB's Oilers in the opening days (and then racing away to Dutch and then East and South along the coast back to Seattle), especially if the KB sticks around to hammer Pearl more than a day. Hard for the KB to chase you if they have no gas and are a long way from home. I've also had success breaking up small island invasions early on, or at least sinking their transports and escorts in the SoPac area between Canton and Lunga. And lastly, yes, I've used them in WitP in the DEI, though it's much tougher there due to LBA. I usually lose my CVs trying to block some invasion in the SRA like PM. And in the DEI, I have a lot of surface groups trying to tear unescorted invasion forces to shreds. I will almost always lose all of the Dutch Navy, and likely all of the USN and British ships that start the game there, in the process... plus a few extra British surface ships (mostly CLs and a couple slow BBs) I send down there. And I will sometimes lose the British CVs should the mini-KB or some other Jap AC group of 2 CVs or less moves into the IO close to Ceylon... but then again, when they send only the CVLs or CVEs... I almost always sink them, and yes even when my CVs are only carrying fulmars and swordfish.
Regarding those cities, no, I don't try to hold them more than normal, unless you count trying to botteneck in the jungle/river hex east of Rangoon in WiTP. And yes, I've kept Rangoon through the whole war in a PBEM. For the most part, I think some players see that some guy did it in an AAR, or saw a post by some guy claiming they did it once, so they try to do it too. I agree with you in that trying to keep Rabaul or Singapore is madness
It also happens from the Japanese side... I've had a Japanese opponent attempt an invasion of Pearl because he read that one famous AAR where it happened, and he ended up losing 2 CVs from the KB in late Jan 42. He then followed it up with 2 failed invasions of Midway where he lost a 3rd CV... this is in addition to the tons of shipping, escorts and LCUs he lost.
Lastly, I've had a game vs. a good japanese opponent where I lost 4 CVs in the first 3 months. He ended up taking from PM, to Noumea, to Suva, to Canton. I was forced to go into build-up mode until mid 43. I was ok with that, but we ended up having a lot of turns where nothing was happening (mostly because very little actually could). The result: HE got bored and quit.
So ya, it cuts both ways