Before I built my computer controlled box joint jig I was experimenting with a simple jig. For this jig I needed a key that has width of my saw blade. I felt that cutting the key on my cheap table saw using a parallel fence was too dangerous. So I came up with the idea to use my cross cut sled instead.
Back then I was using a simple piece of scrap wood that was screwed to my sled as a zero clearance stop block.
I used this method also to cut a strip that has 2 times the width of the saw blade to adjust the key on the simple box joint jig. To do this you simply cut twice when the wood piece is flipped vertical.
This idea can also be used to cut strips for wooden splines.