Ok, for those people out there that really think the upcoming patch for yi is a nerf. Here is a little mathcrafting....
it used to be 30/50/70% multiplicative, now its 40/60/80% additive.
Lets say you have 1.0 atk speed. a 30% multiplicative is 1*1.3 = 1.3 atk speed. A 40% additive is a 1.4 atk speed. With me so far?
In order to be losing out on atk speed for highlander lv 1, you need a base attack speed greater than 1.333... reason? 1.333 * 1.3 = 1.733... 1.333 + .4 = 1.733, fascinating, i know.
now, lets say you already blew through that. you reach the second level of highlander. Here is where it reaches the breaking point. a 50% multiplicative means that at level 2 highlander you need to only have 1.666 atk speed to cap yourself at 2.5 with highlander up... for addative, it means you need a 1.9 atk speed. This is the "nerf zone" so for 9 seconds you have a slight disadvantage of .234 atk speed, is this a problem? not really, 1 dagger will just about get you the boost you are missing out on.
Then there is the 70% mult versus the 80% additive. you need an atk speed of only 1.471 to cap out on your attack speed with highlander level 3. while you need only 1.7 atk speed to cap it with the 80% additive.
What does this give you? better starting off at the gate, because you can get more power with less work. Mid game, it may be a nerf it might not be, it depends on how fed you are. The only people who find this a nerf are those who 1) can't play yi, 2) those who didn't build atk speed cause they relied on an "I win" button, or 3) people who don't play yi, or 4) don't understand that this makes us better at level 6 when we might not have the gear to make a 30% multiplicative worthwhile.
Just to give you an idea, if you hit level 6, got fed, and you built greaves and malady, you would have a 1.304 atk speed, awww too bad, you still get more from the new "nerfed yi". At level 11 with only those items you are at 1.399 atk speed. so now you do 2.099 atk speed. while the patched yi is 1.999 so you lose .1 atk speed. so you lose out on a hit every 10 seconds, oops, the spell only lasts for 9 seconds, guess you didn't lose anything.
Lets say you suck at playing yi so you only have those 2 speed items when you reach 16, at lv 3 highlander you notice the difference. instead of getting capped at 2.5, you end up with 2.295 atk speed. so you are missing out on 2 attacks every 10 seconds.
I understand that many people see multiplicative to additive being a big nerf, but in reality, its a bigger starting buff, an on-par mid-game buff, and as an end buff most people have enough atk speed they could probably drop some speed, add more suvivability and not notice a difference when their ult is up because they are using its innate power instead of letting it get capped and going to waste.