To Kuroyasha,
1 thing I am curious is, is spell speed reduction indeed "tiered"?, just because the tool tip show us 2 decimal points only, does not mean that, in the actual game calculation, they really only use two decimal points.

To illustrate what I mean :
X amount of spell speed = 2.3276 GCD (tool tip shows 2.33)
X + Y amount of spell speed = 2.3256 GCD (tool tip shows 2.33)
X + 2Y amount of spell speed = 2.3236 GCD (tool tip shows 2.32)

So, if they take more than two decimal points in their calculation, we can see that each increment of SS helps ever so slightly, but the tooltip will still show the same value.
Only when we reach break points (aka tiers), the tooltip will update to the next lower value.

Wonder if there's anyway way to properly test out how the use these values =\