I'm with you.
Dan Newberry's OCW test procedure is well thought out and his Practical Rifle forum has a lot of great information.
I've used both ladder and OCW, and for me it is much easier to see where my accuracy nodes are with the OCW method.
One advantage is that you can get good results with the OCW test at 100 yds. For a ladder test to show enough separation on the target 200 yds. is about the minimum.
On a ladder test, with only one round of each powder charge, you can't trust the POI of any of the rounds that are in the "scatter node". This is the point in the barrel vibration sequence where POA and POI deviate the most.
