Some Fundamental Reading

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If it's a talent that provides a 10% dps increase or offers an ability you'll use constantly, fine. It's hard to argue that won't benefit most players. But when I see players obsess over talents that provide a theoretical 1% dps increase that is vastly overshadowed by the noise of their own performance, I shake my head a bit. Want to see what I mean? Compare a parse of yours on the same boss from week to week. You'll probably see a dps variance of 5-10% or more. That's the role of your skill, latency, bad luck, lacking the perfect raid comp or whatever else. Worrying about that 1% dps talent was a rounding error. Let's not forget that what may be 1% on one boss probably is not on another.
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This is something that all min-maxers know: all optimization models used to calculate stat/talent weights are approximations.  And as all approximations they have a domain of applicability and they have limits.
This is where simulationceraft is a nice tool: it doesn't only give you only the "magical" average DPS value, it provides also a distribution.  And from that distribution you can see the +-5% deviation.  And that 5% deviation is in an ideal simulation where everything is perfect.  In a real fight, which is never identical to a simulation (except for Patchwerk with 0 latency), there are a lot more variables which come into play. That 1% is a drop in the ocean.  Sure, it adds water, but good luck if you expect the level to rise.

So, next time someone goes "OMG you have one wrong gem!!!  OMG with another enchant you could gain 0.1% DPS!!!" show them that message.  And if the guy says that he knows better than whoever wrote it, tell him you found it HERE, and that the author is Ghostcrawler and that if he knows better than either he should go and apply for a position at Blizzard, or (a lot more likely) he's an idiot.