Nope. I had 3 new ADF mechanisms fitted under warranty.
I must admit things did seem to improve a little with the replacement ADF's, the last one had a different part number and was listed as "updated", but it physically looked the same.
The underlying problem is there is no register for the paper to "butt" against when you put it in. There is just a single roller in the middle so its far too easy to get the paper in wrong. The whole mechanism needs redesigning in my opinion.
I have just learned to live with it and take much more care when placing scans in the ADF to make sure they look absolutely straight and dont rely on the mechanism keeping it straight for you.