This scared me. LIKE WOAH.
If this is true, how come I'm not yet losing my concentration?
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I can go on without sleeping for [u]4-5 days.[/u]
And don't get me wrong cos I've been doing that for years already.
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Concentration is difficult? And mistakes increase? I don't know.
Haven't experienced it.
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Anyhow, I'm not saying that this is not a proven fact but yeah, it doesn't fit me.