This looks like a great fretboard tapering method

[Dave Bagwill]

I would do this on my bandsaw rather than table saw, but the easy to make jig seems to be very sensible.

http://www.anzlf.com/viewtopic.php?f=5&t=2169

[ken cierp]

Table saw + guard off = injury

[Dave Bagwill]

Yeah it made me wince to look at it. Bandsaw and push sticks is the way to go.

[Robert Hosmer]

Yeah, a blade guard and featherboard hold-down is best for the tablesaw. People tend to use the TS for a cleaner, more accurate cut.
Without a doubt, the bandsaw is considerably safer, albeit with more "cleanup" usually required. Really depends on the blade and how well the saw is set up.

I've used this type of jig many times in the past to taper table legs, etc., and it works fine if used correctly.
The critical point is the amount of extension of the spacer from the main block; the jig needs to be constructed such that the location of the cutoff for the nut contacts the very corner of the spacer.