You must be refering to that nuttin fancy dude on youtube. According to him a knife is useless unless it can baton through logs a couple of feet in diameter.

I used to be a big knife fanatic, But I have long since realized I can achieve the same result from breaking dry wood by hand/foot and that most of the value in batoning/chopping with a knife is just for show and not really necessary.

It is kinda fun dropping a tree and batoning it up into pieces for the fire. It isn't a bad thing to know how to do but in a true life or death situation I believe I would try to get the fire going while expending the least amount of effort.