Here are some more post patch results. All this is from Seb and includes everything from d1 to juggs. Level 60 using 10 damage piercer. I did use duelist a few times but that shouldn't skew the results too much.
[You must be logged in to view images. Log in or Register.]
I know its hard to see.
Out of 1156 backstabs 46.3%(535) were hit for minimum damage.
Only 9.8% were for the magic number of 128.
Definitely too many minimum hits considering the majority of this data is from D1 with a lot of LB mobs.