I'll admit dot snapshotting is clunky and boring but the secondary resources are what turned warlocks from a dot/cooldown class into a long-term strategy class. They'd be idiots to regress to "cast X when it comes of cooldown/when the dot falls off".
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Having two proc trinkets, a proc set bonus, a meta gem proc, and dark soul can drastically affect your doom, which in turn creates pretty noticeable changes in your overall dps. But yes, certainly the problem is more central to affliction.