Originally Posted by
Zephirdd
that's because those three items directly correlate to the value of haste versus mastery.
Erratic Metronome is a glorified haste statstick(although more valuable than one at the same ilvl). Whispers in the Dark works pretty much the same way, giving you a bunch of haste(and with an ultra dynamic class like SP, whispers works really well with our dot damage and toolkit). Shoulders also place you at 3 stacks of VF instantly, further increasing mastery value and therefore decreasing haste value. You effectively have over 11k haste(roughly) with these items, even if the physical value is 8.5k, just because of how they interact with our kit.
And this is a prime example of why 10k haste is NOT mandatory.