I started canning over 20 years ago.  I taught my Old Man several years later.  Memory fades over time if you don't use it.  When I was teaching him, I was going off my personal experience ( I taught myself the canning arts).  Back then we didn't have videos on the internet on how to do things.  I had to go off my interpretation of what I read.  After evacuating the kitchen while the pressure canner was going full tilt, I developed a fear of my canner.  That thing was just out of control.  Volatile to say the least.

The Old Man got to spend this past summer at home.  We had already planted a garden and the fields of professional farmers were coming into fruition.  I had to go back to work full time.  I wasn't about to let these things get in the way of filling my pantry with things I can eat. (I am highly sensitive to A LOT of additives you find in everyday pre-made foods on the supermarket shelf.)  So....he, being the inquisitive sort, did a bunch of research on the internet in between tending the garden and keeping up on housework. 

On point to the subject, he did some research on how a pressure canner should be properly run.  He experimented while I was at work.  I would come home at the end of a 16 hour shift to canned Marina Sauce, Beef Stew, Split Pea Soup, Baked Beans.  It sparked an interest to re-learn my pressure canner.

After some very patient and understanding direction, I have produced 10 quarts of Split Pea Soup this weekend.  Ingredients:  Split Peas, Water, Carrots, Onions, Ham, Allspice, Bay Leaf....in order of ratio to volume.  I like that.  A Lot.