As for Kaeko, that's a different kettle of fish. Note that this isn't intended to bash him in any way, but you did ask me the question so I think I should answer honestly. Outside of a couple of PMs and a recent conversation I don't actually know him at all, and I certainly never played with him so I can't speak about his playstyle first-hand. I'm certain he's very competent, though. But personally, I always admired him because of the fact that he takes initiative, devises strategies for stuff no one thought of before, goes into the mathematics of his undertakings in-depth, and basically goes out and tries stuff - it's not his apparent playing "skill" that's ever been the impressive trait for me, not that I have any right to comment on it as if I have first-hand experience. It always annoyed me (as I'm sure it did most others) when people spouted things like he's "the best BLM in the game" or similar sweeping statements. He stated back when his blog first started getting attention (I think in the NW Apollyon entry) that his BLM didn't even have capped merits, and someone on Odin mentioned a long time ago that they used to see him soloing Zhayolm's Ebony Puddings in AFv2 hat - something most good BLMs understood to be bad practice even a few years ago. Anyway, I'm fairly certain that my old BLM was "better" than his.
Of course, I'm not trying to equate gear and merits with skill; for some reason I felt this was the appropriate place to make those points, even if it's not completely related to what we're actually talking about. I was, however, trying to emphasize the point that it's not Kaeko's playing skill, but rather his initiative and willingness to push boundaries, that deserves credit. Do I think I could devise, test and successfully pull off strategies the way he does? Certainly not. Do I think that, given the same tools as are available to him, I could emulate what he actually does in-game? Probably; I've already done so in the past on my own character, and I'm sure a heck of a lot of people could say the same. Keep in mind that I'm not trying to make myself out to be some kind of FFXI god - what I'm saying about myself applies to all the smart players out there.