Stackable Slot Cutter with top bearing?
I'm hoping this is the appropriate forum for this. In the attached sketch, I show a joint that I do quite a bit for a knockdown bed corner. It's a variety of tongue and groove, cut along the width of 4/4 material. I first do a 3/8"w x 1/4"d on piece 1. Then I dial in the appropriate rabbet on piece 2. It's not a really difficult thing to do; but I was wondering, given the variable of stock thickness, if (using a router dedicated to this task) I could modify a stacked slot cutter to have a top bearing which would ride along the tongue, and provide a consistent 3/8" space, so I wouldn't need to dial in, and I could simply grab the dedicated router and get to work?
Sketch B shows the corner having used a traditional tongue and groove cutter, which ensures accuracy, but leaves less stock at the already weak point.
So my question is practicality, but especially safety.
Thanks in advance