Found a little bug(not so sure if this is can be called a bug)
Now alembic animated can produce nice motion blur,which is great,but when motion blur duration is set to 1.0(default),it lose motion blur randomly(for example,in frame 20 obj has nice mb,but in next frame,it lose mb at all,but try next frame,the mb come back...)so in my test,when 4-5 frames,it will lose 1 frame motion blur!!
But if the motion blur duration is set to 2.0,everything works fine(although 2.0 produce too much mb wich is not what I want,I prefer 1.0!)
