Frenzy attack speed change 2.4

Apparently I missed the attack speed patch for dual wielding in 2.4:

Blizzard wrote:

Changed how attack speed is determined while dual-wielding weapons. Swapping weapons between hands should no longer result in dramatically different attack speeds

Does anybody know how this changes

Frenzy? I still reequip my Death in a

Colossus Sword every game and after every weapon switch. Is this still necessary?

Before 2.4, ias on offhand weapon did not matter. But according to this calculator, it does now https://warren1001.github.io/IAS_Calcul ... 30-0-0-0-0
When I have ias on a

Phase Blade in my main hand, I suddendly need more IAS to reach 10 frames per animation compared to not having ias on it. https://warren1001.github.io/IAS_Calcul ... 30-0-0-0-0

Does anyone have a good link or explanation of those new mechanics?

Okay, that calculator seems broken. It says so in the bug report:
https://github.com/Warren1001/IAS_Calculator/issues/17