Doris, there are people who will can in the oven, but according to.my contacts, (many of them cannot year round) is too dangerous to do with meats, and takes a lot more time and fuel to do.
And there are differences between pressure canners and pressure cookers. You can Can in either, but do not COOK with the aluminum canner. Cookers need to be stainless steel.
The only real difference between a good tracker and a bad tracker is observation. All the same data is present for both. The rest is understanding what you are seeing.