My one side is adjustable Ryan. It will swing +/-25 degrees from 45. That's more swing than it should ever need and once it gets to a certain angle, it wouldn't be practical but I couldn't imagine a scenario where I would need the extremes. And mine will ride the fence (either table saw or router table) so I can adjust position by moving the saw/router fence in any case the work is too big to just use the adjustability in the fence on the jig.
I think the V is to allow it to sit into the V and be held against potential movement with downward pressure as the piece goes through the blade. As we know contact with a TS blade at anything except straight in can get wiggy. Having the V dispenses with a strong suggestion to use clamps, so they are quicker to use.
Probably a single side on a sled, or against the fence could also be safe as long as the piece couldn't move, IE: clamps.
Yeah I could definitely see that George but I'll have a fence on one side and will clamp it to the table either with a quick clamp or maybe with some t-track clamps depending on the size of the work. And spline cuts aren't heavy cuts most of the time so I certainly think it will be sufficient. I'll test it on scrap first just to be sure.
