Unless there's something to gain from IS or AN, I don't see much point in either one. Since there's nothing in the .dat mines worth obtaining, I see less point in campaign than beseiged. At least you can convert IS to coin and sell it when you have no more use for it yourself. AN is basically only good for travel -- which I suppose makes it a good thing that the .dat mines don't show any worthwhile potential for AN. The AN earned versus travel expenses would make it VERY hard to acquire enough for an item.
IMHO, the only reason to rank up in WoTG is in the hopes that they might add something nice for AN in the future. That's a lot of wasted time for "IF", especially considering that you have to live your life in the game due to the decay. Also, there was nothing at all in assault for NIN or THF and only one item was a marginal upgrade via high rank IS for NIN. SE has a very poor track record of giving either of the jobs I play any choice for their gear. Betting on AN would be kinda dumb for me. OTH, if I played WAR, I'd be all over campaign. It's nearly certain there will be a couple nice things in there for that job.
Now that I have captain in ToAU and the IS item I wanted, the only point to besieged is to kill an hour. The XP isn't worth it compared to even a bad XP group and the IS has no value to me other than to convert to coin for sale on AH. If you don't have time to setup a group and go XP, a little besieged works.
If campaign was as easy to reach as besieged I'd use it the same way: a method for minor gains when I have little time. If campaign rank didn't decay, I might consider ranking up. But with the decay, it's an obvious utter waste of time. I really don't want to live in WoTG or be forced into regime of campaign & OPS just to maintain rank.
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