I know how the new HotR work!

HotR damage = DPS x 3

Because it does 3 times DPS, it would essentially do Weapon damage if your weapon speed was 3. Since it used to do 120% weapon damage, this would be a nerf, at weapon speed 3.

It should be a buff.

Its a buff... It encourages us to use the tanking weapons available at 1.6 speed. 1.5 would be Weapon damage x2, essentially, which is a buff from before. At one tenth of a second slower, a 1.6 weapon would be a significantly more powerful weapon for HotR than it was pre-patch.