I can on average about 400 lbs of tomatoes alone, every year plus various other fruits and veggies. After varying levels of success with previously used containers and lids over the years, I use as many glass lids with rubber rings as I can. When I run out of the retaining rings for glass lids, I go with the Bernardin lid sets.
Pickle jars with original lids and the like are not reliable enough. I have a ~0.1 % failure rate with Viceroy rings or Bernardin lids, but a near 15% failure rate re-using factory jars. That is WAY too much waste, as you can only eat so much of the product while processing...
As a scientist you know that once the product is in the jar it starts cooling, and that decreases its volume, so why did you say you are “releasing the pressure” after filling?
If the jar is hot, and the product is hot, and the lid is hot, where is the “air” you are letting out coming from? All you are doing is letting air in, from my experience. Unless I missed something, which is quite possible.
When you’re canning it the nontraditional way, There is air inside heating up and expanding so you have to release that.
This is clearly a method that is not for a serious effort long-term storage. But it works for several weeks worth of canned chili and other things I like to make a large pot of.
Mostly just soups and chili.