Just as the title says. Had a Silent Hunter (29-54, 1.8, +7 agi). Replaced it with a Coldrage Dagger (31-58, 1.5, Frostbolt proc), damage went down about 6 points on the character sheet.
I’ve swapped out gear just to make sure it wasn’t the 7 agi (took some stuff off w/ the former dagger on) and it wasn’t (went down about two points of damage).
Backstabs hit less with the Coldrage too; I thought weapons no longer factored in attack speed when calculating ability/auto damage?
Auto attacks were never normalized as far as I know.
What was normalized was the attack speed used to calculate extra damage on many abilities(some abilities were left unnormalized).
The difference you are seeing in backstabs is likely randomness. 29-54 base is not much different from 31-58. To actually notice the difference you would need to basically do many backstabs with each weapon. Around 500 or so. Then compare the two data sets statistically.