I can see how that would work to hold the ends down tighter, but the center may not be tighter.....but it may not matter if the ends are tight. I've seen a similar method before. The frets were cut to length. When they are installed, the are offset and extend off of the edge of the fretboard by roughly 1/16". Then you tap them in from the side to make them flush with the fretboard edge. Basically the barbs create a downward slot and then to the left or right to create an "L" shape slot. In theory, there will be no missing wood above the barbs and they should hold the wire down tightly.
I use a block of hardwood and the nearest hammer to drive frets. If the outside edges are started straight the center goes down easily. Just keep hammering (within reason) . Keep going until the fret is seated.