I don't have a KJ but saw a demo and I think they are trying to simulate the way you set up hand cut DTs. Seemed pretty natural at the time. Almost bought one. I think you can line it up anyway you want - half tails, half pins. It's up to you. By not using bushings, you see exactly where the cut will be. [edit:] forgot to say - They cut the tails first and then scribe to aid aligning the template for the pins. This should yield a pretty well aligned joint.
I see pros and cons to their approach. It shines because there is so little set up and you align just like cutting by hand. (I really dislike having to do the offset thing on other jigs). On the other hand, they use top guide bearing bits (no bushings) which, I think, means fewer purchase options. It's also cool that you can invert it and use a router table (good for small boxes). They claim no test cuts needed (a huge plus) but I'm a lil skeptical of that.
Measure twice, cut once and CROSS OUT THE WRONG MARKS.
Last edited by PhilBa; 05-01-2016 at 01:59 PM.