I hero edited some small charms with power of 2 attack speed boosts (1-2-4-8…), then i whirlwinded on monsters a bunch, recorded the audio (luckily i can turn off all the audio in the game except combat sounds) and analysed the intervals between hit sounds.
Not sure how to apply this technique for 2-handed weapons because it doesn’t look like they apply. I have no idea how the new whirlwind works for 2-handed weapons.
Here are attack speed breakpoints in 2.4.3 and 2.4 or before, for bases of 20, 10 and 0 base speed
Base at v2.4.3 
|
20 | 10 | 0 | v2.4
|
20 | 10 | 0 |
|---|---|---|---|---|---|---|---|
 Frames per attack |
|||||||
| 14 | 0 | ||||||
| 13 | |||||||
| 12 | 3 | 0 | |||||
| 11 | 0 | ||||||
| 10 | 4 | 0 | 16 | 6 | 0 | ||
| 9 | 13 | 2 | 0 | ||||
| 8 | 26 | 13 | 2 | 26 | 16 | 6 | |
| 7 | 46 | 29 | 15 | ||||
| 6 | 83 | 58 | 39 | 47 | 37 | 27 | |
| 5 | 174 | 125 | 89 | ||||
| 4 | 79 | 69 | 59 |
First off, it’s clear that on the high end there’s a hard cap of 5 Frames. So a nerf to the power level ceiling of 25%.
Second, there is indeed a big boost without attack speed to “slow weapons”. 20-10-0 bases started before to this at 14-12-10, now they do at 11-10-9. Not so much of a boost to 0 bases, but together with the new increased ED% i think it will make whirlwinding at level 30 doable. You also don’t have to find a weapon with IAS anymore, you can use those Death’s or Sigon’s Glove+Belt combo to skip a lot of early breakpoints! Overall, I think this is a great boost to a playthrough version of a single-weapon whrilwind barbarian.
Let’s look at practical end game applications now.
IK set (weapon speed 10)
Before the change, you started at 6 frames per attack, and could down to 4 (50% DPS increase) with 2 Shael runes or IAS jewels strictly in the maul.
Now, you also start at 6 frames (40 IAS from the maul and 25 from the gloves). However to get to 5 Frames, you need to obtain 60 more IAS. If I were to socket the maul with 2 Shael runes, I would still need 20 more IAS. That’s either 2 jewels in the helmet\armor, or a Highlord’s Wrath or a Cat’s Eye amulet. So you get worse results than before and you are limited with gear choice.
It still can be obtained without socketing the maul, if you want (for example, you could put an Um + Lo\Ber\Eth in the maul) - then you need to socket the helmet and the armor with 3 IAS Jewels and you have to use Highlord’s Wrath or Cat’s Eye Amulet.
In essence this gives you an ability to have open wounds on the IK barb while being 20% faster than before (5 frames vs 6). My desire was to do ubers on IK barb (open wounds is mandatory for mephisto and lillith that cannot be poisoned), but i don’t feel like I’d be able to take down mephisto with this setup anyway, because I won’t have free sockets in my helmet or armor for Lo runes (to increase the lightning resist). Wearing 2 wisps projectors would probably help… but honestly with this many sacrifices I’d prefer the old 6 frame attack speed (wisps is crazy rare and doesn’t give attack rating)
BotD
My favorite BotD base was Ghost Spear. I just like spears, what can I say. Whirlwinding with a spear looks odd though… spear would get stuck in the enemies. Still looks cool, I’ll suspend my disbelief. On top of that if you make BotD Ghost Spear you could use it on most amount of characters - barb, druid, merc and amazon.
Prior to this just the 60 IAS on the BotD Ghost Spear would let you have max speed of whirlwinding, i.e. 4 frames per attack.
Now you have to have 81, and with the unfortunate 81 IAS breakpoint for 0 speed base means you’ll need to wear 2 IAS pieces to max the attack speed. Cannot just do away with a highlords, have to have a goldwrap, for example. You could ofcourse just wear m’avina’s helmet or treachery, but those item slots are way too valuable for that.
What about BotD war pike? well… it’s in the dumpster. Nobody’s getting 174 IAS. You’re doomed to spin at 6 FPA, which you could do before without any extra IAS gear, and now you’ll need 2 pieces for +23 more on top of the BotD.
Conclusion
New whirlwind still needs a lot of analysis, like how dual wielding works, and what’s gonna happen with faster weapons, and need to actually try the playthrough version.
But on the 2-handed end-game side of things, on the IK side of things… looks like a moderate nerf to me.
My IK barb (2xShael in the maul, angelic rings+amulet) on HC Ladder is still playable though. I can just unsocket those Shael runes from the maul now, cuz they aren’t doing anything at all (65->105 isn’t a breakpoint).
