I was referring to a Satterlee method "ladder," where you find your node based on velocity flat spots. I've never had as much luck with a traditional Dan Newberry OCW which is akin to the Audette method, which is the ladder you must have been referring to, I don't have the range access for the Audette method. I have mentally blurred the two over the years.
I have tried an Optimal barrel time method and have had good luck with that using quick load. Frequently, the nodes from the Satterlee method come in near an OBT point. However, it isn't necessary an OBT point for the exact barrel length, ie 26 or 28 (being 26 with 2 for a brake). Also, if I get velocity flat from the Satterlee method, that isn't near an OBT node, it usually won't give as good or as consistent of results as one that is near an OBT point
What has kept me from getting a Labradar, has been the folks I've seen at the range with them, and their consistent complaint of picking up other shots. I'm glad to hear there is a way to tune that out. When my magneto speed gives out, I will definitely look at getting one.