The tenon saw is a right handy tool when it's sharp, and fairly useless when dull. The ways of the world are such that it's easier, less time consuming and relatively cheaper, simply to purchase a new saw when the old one becomes blunt, than to learn how to sharpen the teeth and buy the necessary honing tools—at least that's what they tell me at the local hardware outlet.
It's not parsimony, though I live frugally, but a desire to keep the tools I already have that has lead me to embark on this restoration of The Invisible Workshop. And saw sharpening looks easy in the youtube video, though my saw became still duller after the first attempt. However, with practice and patience I might sometime achieve a solid work surface and sharp tools. Yes, we've heard it all before.
I look at these Swedes, from long before someone thought to flatpack furniture, and am struck with wonder.
I got the rebate plane working and made a lap joint out of some cruddy pallet pine.