It's all a practice thing. I haven't turned wrenches for a few years, but was teaching my older boy last month how to use different styles of torque wrenches. When I tightened down with a ratchet and had him use a beam style to loosen it I questioned the tool, because I used to be crazy accurate. I ment to tighten to 75lbs, but went to 82. I did a "35" and it was 38 using another torque wrench to check it. Kills me, I was always within 1 pound all the way to 250 lbs range, and figuring the 1% standard error rule- that was something I showed off with to friends.
It's a practice thing like shooting or playing an instrument is. Torque wrenches recal rule is once a year, everytime dropped, or 1,000 cycles.
Want to get better- waste $15. Buy a harbor freight throw away one, compare it to your real one to make sure it's in spec, double check your monthly. Most HF are 5-6% off new and 10% off in a year I learned when working for a large company that only bought HF tools when I started there (into my 2nd year I had them off the crack). Use the HF one as a ratchet for everything you do for a while. You'll get the feel real soon. Then you have a loaner for the neighbor who doesn't understand to take care of stuff. You'll also learn why you don't buy accurate tools at HF.
On the air tool usage, I get close with them but worked with guys that had a feel for it and can be within a couple pounds everytime using impacts. Usually grey hair and very faded toolboxes was involved
