Wow, interesting technique I've never seen before.
I've used both french fuse type tricot and Pellon 906F. The tricot has a different hand and is a little thicker but, other than that, I think you could use the Pellon -- especially if it's for a wallhanging. It serves as the foundation for the piece, so it won't show. She did mention that they found the French Fuse had more forgiving adhesive than other types; might make a difference if you need to shift or substitute pieces.
I think overlapping by 1/4" would work fine. You could even overlap by 1/2" and I don't think it would make any difference at all. Just be sure to work with parchment paper on both sides so you don't glue the fusible to your ironing board or iron. Be careful to peel off the parchment paper while the fusible is still warm.
To be absolutely sure, you should test fuse a couple of small pieces together, then work the technique on that piece (maybe substituting a couple of fused-down pieces) to make sure it will all work as planned on your big piece.