I'm all for new tricks and toys, but sometimes, some of the old ways are truly better. When removing a T&G board, instead of attempting to stop midway to the end butt, just remove the entire board, end to end. It was Daniel Boone, one time technical director of the NWFA that showed me years ago to cut two parallel cuts about 3/8" in from the edges to cut through the fasteners. Make your parallel cuts from one end butt to the other, without going past of course. Now contect the two parallel cuts with a diagonal cut starting at one end and finishing at the other. You will be able to simply lift the two center pieces out without much effort. The groove side should just side toward the center for easy removal. The tongue side will require using a chisel to tap toward the center as, even though the fasteners are cut, they still hold the tongue into the groove somewhat. Now if you need to cut a board in half and cannot remove it all the way from end to end, simply scribe the non-factory end you plan on cutting with a square. Scribe it deep. Then either use two large drilled holes on each side and clean it up with a chisel OR just chisel it out. With a sharp chisel, I can cut cleanly and squarely through a 3/4" x 2.25" board in a couple of minutes. It probably takes a little more effort but I doubt anymore time considering that if using an electric saw, you'd need to go to your truck, get the saw and cord, install a new blade and make the cut. I'd be done by the time you had your saw set-up and ready. Now if you had to make multiple cuts, I can see that it would be an advantage. But then I would be planning to remove the boards from end to end. A good chisel costs about $7 to 10 and I sharpen it myself with my portable belt sander. I don't know, maybe it is hard to teach an old dog new tricks.